**4. Result and discussion**

#### **4.1. Experiment # 1 (screening analysis)**

Experiment 1 was conducted for screening analysis to select best wheat genotypes. Highest germination percentage was recorded for T2 (87.78%) followed by T1 (87.03) while lowest was at T4 (80.1%) (**Table 1**). There was 20% difference among T2 and T4. In the meanwhile, all the genotypes behaved differently for germination percentage. Maximum germination (96.67%) was recorded for genotype NARC-2009 while minimum germination percentage (76.50%) was recorded for genotype Dhurabi. There was 8% difference among genotype NARC-2009 and Dhurabi for germination percentage. The interactive effects were statistically significant at 1% P level. Maximum germination percentage was recorded for NARC-2009 (100%) at T1 and T2 while minimum germination percentage was recorded for genotype BARS-09 (66.67%) under T1. The treatments depicted significant effect on root fresh weight of different genotypes. All the genotypes varied considerably for root fresh weight (RFW) (**Table 2**). Maximum root fresh weight was recorded for genotype NARC-2009 (0.12 g) while minimum root fresh weight was recorded for genotype Lasani-08 (0.09 g). There was 24% difference among NARC-2009 and Lasani-08 for root fresh weight. Similarly, all the treatments differed potentially for root fresh weight. Maximum root fresh weight was recorded for T1 (0.11 g) while minimum root fresh weight was observed under T3 (0.08 g). In the same way the interactive effects for root fresh weight was potentially significant at 1% P level. Maximum root fresh weight was recoded for genotype NARC-2009 under T1 (0.14 g) followed by genotype Sehar-06 under T2 while minimum root fresh weight (0.06 g) was recorded for genotype Lasani-08 under T4. Results depicted significant variation for root length for different treatments on wheat


**Table 1.** Germination percentage for nine wheat genotypes under four treatments (T1 = control, T2 = PEG−0.50, T3 = (PEG−1.48) and T4 = (PEG−2.95)).

genotypes at three leaf stage. All the treatments differed significantly for root length at three leaf stage (Z-13) for wheat crop (**Table 3**). Maximum root length recorded for T2 (10.9 cm)

whereas, minimum root length recorded for T4 (9.6 cm) at three leaf stage. Meanwhile, wheat genotypes differed significantly for root length. Genotype NARC-2009 obtained maximum root length (13.9 cm) at three leaf stage however, genotype Lasani-08 obtained minimum root length (8.3 cm). The interactive effect G x T was highly significant at 1% P level. Maximum root length was recorded for Sehar-06 under T1 (14.5 cm) followed by NARC-2009 under T4 (14.0 cm) whereas, minimum root length was recorded for Lasani-08 under T4 (4.5 cm).

**Table 3.** Root fresh weight for 9 wheat genotypes under 4 treatments (T1 = control, T2 = PEG−0.50, T3 = (PEG−1.48) and

**Genotypes Control PEG−0.50 PEG−1.48 PEG−2.95 Mean** Dhurabi 6.56p–r 14.20ab 8.73l–p 6.52qr 9.00EF Fareed-06 10.97e–k 10.53f–l 11.27d–j 12.07b–i 11.21C NARC-11 7.07n–q 8.83k–o 9.23j–n 12.5a–f 9.43DE Sehar-06 14.54a 10.41f–l 13.29a–d 11.25d–j 12.38B Punjab-11 12.55a–g 12.42a–i 10.39g–l 6.70o–r 10.52CD Wafaq-2001 11.67d–i 8.95k–n 8.73l–p 7.93m–q 9.32EF NARC-2009 12.83a–e 14.24ab 14.54a 14.04a–c 13.92A BARS-09 9.2j–n 7.45n–q 9.9i–m 10.35h–l 9.23EF Lasani-08 10.23h–l 11.94c–i 6.42qr 4.51r 8.28F Mean 10.62A 10.99A 10.28AB 9.55B

Effect of Phosphorus on Root Signaling of Wheat under Different Water Regimes

http://dx.doi.org/10.5772/intechopen.75806

9

LSD for G 1.0972 LSD for T 0.7315 LSD for G × T 2.1944

T4 = (PEG−2.95)).

Results illustrated significant difference for shoot length for different treatments on wheat genotypes at three leaf stage. All the treatments differed potentially for shoot length (**Table 4**). Maximum shoot length was recorded for T1 (10.8 cm) while minimum shoot length was recorded for T3 (7.9 cm). In the same way all the wheat genotypes varied considerably for shoot length. Highest shoot length was observed for NARC-2009 (11.7 cm) followed by Sehar-06 (11.1 cm) whereas, lowest shoot length was observed for genotype Lasani-08 (8.4 cm). There was 29% difference among genotypes for shoot length. In the meanwhile, the interactive effect was highly significant for shoot length. Highest shoot length was recorded under T1 for NARC-2009 (13.0 cm) while lowest shoot length was recorded under T4 for Lasani-08

All the treatments varied considerably for shoot fresh weight (**Table 5**). Maximum shoot fresh weight was recorded for T1 (0.21 g) while minimum weight was recorded for T4 (0.15 g). There was 27% difference among different treatments. Highest shoot fresh weight was gained by genotype NARC-2009 (0.23 g) while lowest shoot fresh weight gained by genotype Dhurabi (0.15 g). There was 35% difference among genotypes for shoot fresh weight. The interactive effect was significantly different under all the treatments. Highest shoot fresh weight was

(5.6 cm). There was 56% difference among genotypes under different treatments.


**Table 2.** Root length for 9 wheat genotypes under 4 treatments (T1 = control, T2 = PEG−0.50, T3 = (PEG−1.48) and T4 = (PEG−2.95)).


**Table 3.** Root fresh weight for 9 wheat genotypes under 4 treatments (T1 = control, T2 = PEG−0.50, T3 = (PEG−1.48) and T4 = (PEG−2.95)).

whereas, minimum root length recorded for T4 (9.6 cm) at three leaf stage. Meanwhile, wheat genotypes differed significantly for root length. Genotype NARC-2009 obtained maximum root length (13.9 cm) at three leaf stage however, genotype Lasani-08 obtained minimum root length (8.3 cm). The interactive effect G x T was highly significant at 1% P level. Maximum root length was recorded for Sehar-06 under T1 (14.5 cm) followed by NARC-2009 under T4 (14.0 cm) whereas, minimum root length was recorded for Lasani-08 under T4 (4.5 cm).

**Genotypes Control PEG−0.50 PEG−1.48 PEG−2.95 Mean** Dhurabi 0.08i–n 0.10g–l 0.010e–k 0.10d–j 0.09BC Fareed-06 0.12b–d 0.09h–m 0.08k–o 0.10b–h 0.09B NARC-11 0.10b–h 0.10c–i 0.07l–p 0.07m–p 0.08BC Sehar-06 0.12a–c 0.11b–d 0.10b–g 0.12ab 0.11A Punjab-11 0.12b–d 0.09g–m 0.07n–p 0.07m–p 0.09C Wafaq-2001 0.11b–e 0.10d–j 0.07n–p 0.06op 0.08C NARC-2009 0.14a 0.14a 0.09f–l 0.12ab 0.12A BARS-09 0.10b–h 0.10b–h 0.08j–m 0.09f–l 0.09B Lasani-08 0.11b–f 0.10b–h 0.07l–p 0.06p 0.09C

**Genotypes Control PEG−0.50 PEG−1.48 PEG−2.95 Mean** Dhurabi 73.33e–g 76.67d–g 86.67a–e 73.33e–g 77.5CD Fareed-06 80c–g 86.67a–e 83.33b–f 86.67a–e 84.17BC NARC-11 96.67ab 93.33a–c 90a–d 73.33e–g 88.33B Sehar-06 90a–d 80c–g 93.33a–c 93.33a–c 89.17B Punjab-11 90a–d 93.33a–c 86.67a–e 80c–g 87.5B Wafaq-2001 96.67ab 93.33a–c 83.33b–f 80c–g 88.33B NARC-2009 100a 100a 93.33a–c 93.33a–c 96.67A BARS-09 66.67g 76.67d–g 86.67a–e 76.67d–g 76.67D Lasani-08 90a–d 90a–d 66.67g 70fg 79.17CD

Mean 87.04A 87.78A 85.56A 80.74B

LSD for G 6.7819 LSD for T 4.5213 LSD for G × T 13.564

8 Global Wheat Production

T3 = (PEG−1.48) and T4 = (PEG−2.95)).

genotypes at three leaf stage. All the treatments differed significantly for root length at three leaf stage (Z-13) for wheat crop (**Table 3**). Maximum root length recorded for T2 (10.9 cm)

**Table 1.** Germination percentage for nine wheat genotypes under four treatments (T1 = control, T2 = PEG−0.50,

Mean 0.11A 0.10B 0.08D 0.09C

**Table 2.** Root length for 9 wheat genotypes under 4 treatments (T1 = control, T2 = PEG−0.50, T3 = (PEG−1.48) and

LSD for G 0.00904 0.242374 LSD for T 0.006027 0.250676 LSD for G × T 0.0181 0.569639

T4 = (PEG−2.95)).

Results illustrated significant difference for shoot length for different treatments on wheat genotypes at three leaf stage. All the treatments differed potentially for shoot length (**Table 4**). Maximum shoot length was recorded for T1 (10.8 cm) while minimum shoot length was recorded for T3 (7.9 cm). In the same way all the wheat genotypes varied considerably for shoot length. Highest shoot length was observed for NARC-2009 (11.7 cm) followed by Sehar-06 (11.1 cm) whereas, lowest shoot length was observed for genotype Lasani-08 (8.4 cm). There was 29% difference among genotypes for shoot length. In the meanwhile, the interactive effect was highly significant for shoot length. Highest shoot length was recorded under T1 for NARC-2009 (13.0 cm) while lowest shoot length was recorded under T4 for Lasani-08 (5.6 cm). There was 56% difference among genotypes under different treatments.

All the treatments varied considerably for shoot fresh weight (**Table 5**). Maximum shoot fresh weight was recorded for T1 (0.21 g) while minimum weight was recorded for T4 (0.15 g). There was 27% difference among different treatments. Highest shoot fresh weight was gained by genotype NARC-2009 (0.23 g) while lowest shoot fresh weight gained by genotype Dhurabi (0.15 g). There was 35% difference among genotypes for shoot fresh weight. The interactive effect was significantly different under all the treatments. Highest shoot fresh weight was


**Table 4.** Shoot length for 9 wheat genotypes under 4 treatments (T1 = control, T2 = PEG−0.50, T3 = (PEG−1.48) and T4 = (PEG−2.95)).

accumulated for genotype NARC-2009 under T1 and T2 (0.26 g) while minimum was accumulated for Lasani-08 under T4 (0.11 g).

The treatments varied statistically for shoot dry weight (**Table 6**). Highest shoot dry weight was observed under T1 (0.05 g) while minimum shoot dry weight recorded for T3 (0.04 g). In the same way, genotypes varied potentially for shoot dry weight. The highest shoot dry weight was recorded for genotype NARC-2009 (0.06 g) while, lowest shoot dry weight was recorded for genotype Lasani-08 (0.04 g). There was 23% difference among genotypes for shoot dry weight. In the meanwhile, the interactive effects differed considerably for shoot dry weight under all the treatments. Maximum shoot dry weight was accumulated by NARC-2009 under T1 (0.06 g) whereas, minimum shoot dry weight was accumulated by Lasani-08

**Table 6.** Shoot dry weight for 9 wheat genotypes under 4 treatments (T1 = control, T2 = PEG−0.50, T3 = (PEG−1.48) and

**Genotypes Control PEG−0.50 PEG−1.48 PEG−2.95 Mean** Dhurabi 0.06h–l 0.07d–j 0.06j–m 0.04lm 0.06C Fareed-06 0.09d–i 0.07e–j 0.07h–l 0.04lm 0.07C NARC-11 0.07g–k 0.08c–g 0.06j–m 0.05k–m 0.07C Sehar-06 0.10ab 0.09bc 0.09b–d 0.09b–e 0.09A Punjab-11 0.09b–f 0.07e–j 0.06k–m 0.06l–m 0.07BC Wafaq-2001 0.08c–f 0.08c–h 0.06k–m 0.05lm 0.07BC NARC-2009 0.12a 0.12a 0.08d–h 0.10ab 0.10A BARS-09 0.08d–h 0.09c–f 0.07g–k 0.07f–k 0.08B Lasani-08 0.08c–g 0.09c–f 0.06i–m 0.04m 0.07BC

Effect of Phosphorus on Root Signaling of Wheat under Different Water Regimes

http://dx.doi.org/10.5772/intechopen.75806

11

Mean 0.09A 0.08A 0.07B 0.06B

The results depicted that there was great difference among treatments and genotypes for root dry weight (**Table 7**). Maximum root dry weight was accumulated for T4 (0.05 g) while minimum root dry weight was recorded for T3 (0.04 g). Similarly, all the genotypes varied potentially for root dry weight. Highest root dry weight was accumulated by genotype NARC-2009 (0.06 g) fallowed by Sehar-06 (0.52 g) while lowest by Lasani-08 (0.04 g). In the same way, the interactive effect for T × G was highly significant. Maximum root dry weight was obtained by NARC-2009 under T4 (0.06 g) while minimum root dry weight was obtained by Lasani-08 under T4 (0.23 g). Maximum root to shoot ratio for fresh weight calculated for T1 (1.08) while minimum was calculated for T3 (0.81) (**Table 8**). In the same way all the genotypes differed significantly for root to shoot ratio. Highest root to shoot ratio was calculated for Dhurabi (1.10) whereas, lowest was calculated for Punjab-11 (0.81). Meanwhile, the interactive effects were highly significant at 1% P level. Highest root to shoot ratio was calculated for NARC-11 under T1 (1.57) while lowest for Wafaq-2001 under T4 (0.76). On the basis of screening results two genotypes were selected for experiment II. Genotypes NARC-2009 and Sehar-06 per-

formed better under treatment 4 so these two genotypes were selected.

under T4 (0.02 g).

T4 = (PEG−2.95)).

LSD for G 0.008949 LSD for T 0.005966 LSD for G × T 0.0179


**Table 5.** Shoot fresh weight for 9 wheat genotypes under 4 treatments (T1 = control, T2 = PEG−0.50, T3 = (PEG−1.48) and T4 = (PEG−2.95)).


**Genotypes Control PEG−0.50 PEG−1.48 PEG−2.95 Mean** Dhurabi 8.2j–o 8.7h–m 9.13f–l 9.63e–k 8.92BCD Fareed-06 11.07b–e 8.53i–n 7.57l–p 9.9c–j 9.27BC NARC-11 9.9c–j 9.8d–j 7.33m–q 6.9n–q 8.48CD Sehar-06 11.44a–d 11b–e 10.30b–g 11.59a–c 11.08A Punjab-11 11.04b–e 8.62h–n 6.65o–q 6.90n–q 8.30D Wafaq-2001 10.83b–f 9.56e–k 6.62o–q 6.02pq 8.26D NARC-2009 13.04a 13.039a 8.92g–m 11.64ab 11.66A BARS-09 11.23b–e 10.03b–i 8.02k–o 9.03g–m 9.58B Lasani-08 10.53b–g 9.93b–i 7.32m–q 5.62q 8.35D

Mean 10.81A 9.91B 7.98D 8.58C

**Table 4.** Shoot length for 9 wheat genotypes under 4 treatments (T1 = control, T2 = PEG−0.50, T3 = (PEG−1.48) and

accumulated for genotype NARC-2009 under T1 and T2 (0.26 g) while minimum was accu-

**Table 5.** Shoot fresh weight for 9 wheat genotypes under 4 treatments (T1 = control, T2 = PEG−0.50, T3 = (PEG−1.48) and

**Genotypes Control PEG−0.50 PEG−1.48 PEG−2.95 Mean** Dhurabi 0.16i–m 0.17g–l 0.15k–o 0.12no 0.15D Fareed-06 0.19b–i 0.17g–l 0.15k–n 0.12no 0.15D NARC-11 0.17h–m 0.19c–j 0.15k–o 0.14l–o 0.16D Sehar-06 0.23a–c 0.22b–d 0.20b–g 0.19b–h 0.21B Punjab-11 0.22b–d 0.17g–l 0.13m–o 0.14l–o 0.16D Wafaq-2001 0.21b–e 0.19d–j 0.13m–o 0.12no 0.16D NARC-2009 0.26a 0.26a 0.18f–k 0.23ab 0.23A BARS-09 0.12b–h 0.19b–h 0.16j–m 0.18e–k 0.18C Lasani-08 0.21b–f 0.19b–h 0.15k–o 0.11o 0.17D

Mean 0.21A 0.20A 0.15B 0.15B

LSD for G 0.8636 LSD for T 0.5757 LSD for G × T 1.7272

10 Global Wheat Production

mulated for Lasani-08 under T4 (0.11 g).

LSD for G 0.0179 LSD for T 0.012 LSD for G × T 0.0359

T4 = (PEG−2.95)).

T4 = (PEG−2.95)).

**Table 6.** Shoot dry weight for 9 wheat genotypes under 4 treatments (T1 = control, T2 = PEG−0.50, T3 = (PEG−1.48) and T4 = (PEG−2.95)).

The treatments varied statistically for shoot dry weight (**Table 6**). Highest shoot dry weight was observed under T1 (0.05 g) while minimum shoot dry weight recorded for T3 (0.04 g). In the same way, genotypes varied potentially for shoot dry weight. The highest shoot dry weight was recorded for genotype NARC-2009 (0.06 g) while, lowest shoot dry weight was recorded for genotype Lasani-08 (0.04 g). There was 23% difference among genotypes for shoot dry weight. In the meanwhile, the interactive effects differed considerably for shoot dry weight under all the treatments. Maximum shoot dry weight was accumulated by NARC-2009 under T1 (0.06 g) whereas, minimum shoot dry weight was accumulated by Lasani-08 under T4 (0.02 g).

The results depicted that there was great difference among treatments and genotypes for root dry weight (**Table 7**). Maximum root dry weight was accumulated for T4 (0.05 g) while minimum root dry weight was recorded for T3 (0.04 g). Similarly, all the genotypes varied potentially for root dry weight. Highest root dry weight was accumulated by genotype NARC-2009 (0.06 g) fallowed by Sehar-06 (0.52 g) while lowest by Lasani-08 (0.04 g). In the same way, the interactive effect for T × G was highly significant. Maximum root dry weight was obtained by NARC-2009 under T4 (0.06 g) while minimum root dry weight was obtained by Lasani-08 under T4 (0.23 g). Maximum root to shoot ratio for fresh weight calculated for T1 (1.08) while minimum was calculated for T3 (0.81) (**Table 8**). In the same way all the genotypes differed significantly for root to shoot ratio. Highest root to shoot ratio was calculated for Dhurabi (1.10) whereas, lowest was calculated for Punjab-11 (0.81). Meanwhile, the interactive effects were highly significant at 1% P level. Highest root to shoot ratio was calculated for NARC-11 under T1 (1.57) while lowest for Wafaq-2001 under T4 (0.76). On the basis of screening results two genotypes were selected for experiment II. Genotypes NARC-2009 and Sehar-06 performed better under treatment 4 so these two genotypes were selected.


**Table 7.** Root dry weight for 9 wheat genotypes under 4 treatments (T1 = control, T2 = PEG−0.50, T3 = (PEG−1.48) and T4 = (PEG−2.95)).

> primarily dependent upon biotic and abiotic environment prevailing in the vicinity of plants. Roots are the main source of nutrients supply to the plant nutrients to the plant. Our results were in line with earlier work who was of the point of view that phosphorus has been reported to increase the strength of cereal straw, stimulate root development, promote flowering, fruit production, and formation of seed and hasten maturity of the crops [13]. Due to increased availability of P leaf area, green pigments also increased and hence the shoot length increased finally. Our results were supported by Zhang et al. [49] who reported that deficiency of P

> **Table 8.** Shoot to root ratio for 9 wheat genotypes under 4 treatments (T1 = control, T2 = PEG−0.50, T3 = (PEG−1.48) and

**Genotypes Control PEG−0.50 PEG−1.48 PEG−2.95 Mean** Dhurabi 1.26b–d 0.62mn 1.05d–h 1.49ab 1.10A Fareed-06 1.01d–j 0.84g–m 0.67k–n 0.83g–m 0.84C NARC-11 1.57a 1.13c–f 0.83g–m 0.55n 1.02AB Sehar-06 0.79i–n 1.08d–g 0.78i–n 1.03d–i 0.92BC Punjab-11 0.88f–l 0.69k–n 0.64l–n 1.03d–i 0.81C Wafaq-2001 0.93e–k 1.07d–h 0.76j–n 0.76j–n 0.88C NARC-2009 1.02d–j 0.92e–k 0.62l–n 0.83g–m 0.85C BARS-09 1.22cd 1.35a–c 0.81h–m 0.88g–m 1.06A Lasani-08 1.03d–i 0.83g–m 1.14c–e 1.24b–d 1.06A

Effect of Phosphorus on Root Signaling of Wheat under Different Water Regimes

http://dx.doi.org/10.5772/intechopen.75806

13

Mean 1.08A 0.95B 0.81C 0.96B

Both the genotypes varied considerably for root length (**Table 10**) at three leaf stage. Maximum root length was calculated for NARC-2009 (4.3 cm) whereas, minimum root length (3.6 cm) calculated for Sehar-06. There was 14% difference among both the genotypes. Similarly, there was a major difference among all the treatments. Maximum root length (4.6 cm) calculated for treatment T7, minimum root length (3.2 cm) calculated for treatment T1 followed by T2. There was 31% difference among maximum and minimum treatments for root length. The interactions were significant at 1% P level for root length. Highest root length was recorded for NARC-2009 under T7 (4.8 cm) while lowest root length recorded for Sehar-06 (2.9 cm). Wheat genotypes varied considerably for root length at anthesis stage (**Table 10**). Genotype NARC-2009 accumulated highest root length (43.0 cm) whereas, genotype Sehar-06 accumulated lowest root length (35.3 cm). The percentage difference among both genotypes for number of seeds per spike was 18%. In the meanwhile, all the treatments varied noticeably for

reduced photosynthetic efficiency in wheat due to reduction in leaf area expansion.

*4.2.2. Root length*

T4 = (PEG−2.95)).

LSD for G 0.1294 LSD for T 0.0863 LSD for G × T 0.2588

#### **4.2. Polythene bags results**

#### *4.2.1. Shoot length*

NARC-2009 exhibited maximum shoot length (6.28) at three leaf stage than Sehar-06 (5.28) (**Table 9**). All the treatments showed significant difference for shoot length at three leaf stage. Highest shoot length was recorded for T7 (8.1 cm) followed by T6 and T8 while lowest shoot length shoot length was recorded for T1 (3.47). In the same way, the interactive effect was also found significant. Maximum shoot length was recorded for NARC-2009 under T7 (8.8 cm) followed by NARC-2009 under T8 (8.54 cm) and Sehar-06 under T7 (8.40 cm) whereas, minimum shoot length was recorded for Sehar-06 under T1 (3.1 cm). NARC-2009 exhibited higher shoot length (63.75 cm) than Sehar-06 (54.37 cm). Meanwhile, all the treatments exhibited significant difference for shoot length at anthesis stage (**Table 9**). Highest shoot length was recorded for T7 (69.00 cm) followed by T8 (64.45), T5 (59.88 cm) and T6 (59.11 cm) while lowest shoot length was recorded by T1 (47.61 cm). In the same way, the interactive effects were varied potentially. Highest shoot length was recorded for NARC-2009 (71.64 cm) under T7 while lowest shoot length was recorded for Sehar-06 under T1 (42.88 cm). Maximum shoot length calculated for NARC-2009 (63.75 cm) while minimum shoot length was calculated for Sehar-06 (54.37 cm) (**Table 9**). In the meanwhile, all the treatments differed significantly for shoot length at maturity stage. Highest shoot length was calculated for T7 (75.21 cm) followed by T8, T5, T4 and T6 while, lowest was calculated for T1 (51.89 cm). Meanwhile, the interactive effects were highly significant at 1% P level. Highest shoot length was calculated for NARC-2009 under T7 (78.08 cm) while lowest for Sehar-06 under T1 (46.74). Crop growth and development is


**Table 8.** Shoot to root ratio for 9 wheat genotypes under 4 treatments (T1 = control, T2 = PEG−0.50, T3 = (PEG−1.48) and T4 = (PEG−2.95)).

primarily dependent upon biotic and abiotic environment prevailing in the vicinity of plants. Roots are the main source of nutrients supply to the plant nutrients to the plant. Our results were in line with earlier work who was of the point of view that phosphorus has been reported to increase the strength of cereal straw, stimulate root development, promote flowering, fruit production, and formation of seed and hasten maturity of the crops [13]. Due to increased availability of P leaf area, green pigments also increased and hence the shoot length increased finally. Our results were supported by Zhang et al. [49] who reported that deficiency of P reduced photosynthetic efficiency in wheat due to reduction in leaf area expansion.

#### *4.2.2. Root length*

**4.2. Polythene bags results**

LSD for G 0.00488 LSD for T 0.003254 LSD for G × T 0.009761

NARC-2009 exhibited maximum shoot length (6.28) at three leaf stage than Sehar-06 (5.28) (**Table 9**). All the treatments showed significant difference for shoot length at three leaf stage. Highest shoot length was recorded for T7 (8.1 cm) followed by T6 and T8 while lowest shoot length shoot length was recorded for T1 (3.47). In the same way, the interactive effect was also found significant. Maximum shoot length was recorded for NARC-2009 under T7 (8.8 cm) followed by NARC-2009 under T8 (8.54 cm) and Sehar-06 under T7 (8.40 cm) whereas, minimum shoot length was recorded for Sehar-06 under T1 (3.1 cm). NARC-2009 exhibited higher shoot length (63.75 cm) than Sehar-06 (54.37 cm). Meanwhile, all the treatments exhibited significant difference for shoot length at anthesis stage (**Table 9**). Highest shoot length was recorded for T7 (69.00 cm) followed by T8 (64.45), T5 (59.88 cm) and T6 (59.11 cm) while lowest shoot length was recorded by T1 (47.61 cm). In the same way, the interactive effects were varied potentially. Highest shoot length was recorded for NARC-2009 (71.64 cm) under T7 while lowest shoot length was recorded for Sehar-06 under T1 (42.88 cm). Maximum shoot length calculated for NARC-2009 (63.75 cm) while minimum shoot length was calculated for Sehar-06 (54.37 cm) (**Table 9**). In the meanwhile, all the treatments differed significantly for shoot length at maturity stage. Highest shoot length was calculated for T7 (75.21 cm) followed by T8, T5, T4 and T6 while, lowest was calculated for T1 (51.89 cm). Meanwhile, the interactive effects were highly significant at 1% P level. Highest shoot length was calculated for NARC-2009 under T7 (78.08 cm) while lowest for Sehar-06 under T1 (46.74). Crop growth and development is

**Table 7.** Root dry weight for 9 wheat genotypes under 4 treatments (T1 = control, T2 = PEG−0.50, T3 = (PEG−1.48) and

**Genotypes Control PEG−0.50 PEG−1.48 PEG−2.95 Mean** Dhurabi 0.04e–o 0.04f–k 0.04f–k 0.04f–k 0.04B Fareed-06 0.05c–g 0.04f–m 0.03i–p 0.04f–k 0.04B NARC-11 0.04f–j 0.04e–h 0.032k–p 0.03n–p 0.04B Sehar-06 0.06a–d 0.05b–e 0.05e,f 0.06a–c 0.05A Punjab-11 0.05c–g 0.04f–l 0.03l–p 0.03m–p 0.04B Wafaq-2001 0.05d–g 0.04e–i 0.03m–p 0.03op 0.04B NARC-2009 0.06a 0.06ab 0.04e–i 0.06a–c 0.06A BARS-09 0.04e–i 0.05e–g 0.04h–n 0.04g–n 0.04B Lasani-08 0.04e–h 0.05e–h 0.03j–p 0.02p 0.04B

Mean 0.05A 0.05A 0.04B 0.04B

*4.2.1. Shoot length*

T4 = (PEG−2.95)).

12 Global Wheat Production

Both the genotypes varied considerably for root length (**Table 10**) at three leaf stage. Maximum root length was calculated for NARC-2009 (4.3 cm) whereas, minimum root length (3.6 cm) calculated for Sehar-06. There was 14% difference among both the genotypes. Similarly, there was a major difference among all the treatments. Maximum root length (4.6 cm) calculated for treatment T7, minimum root length (3.2 cm) calculated for treatment T1 followed by T2. There was 31% difference among maximum and minimum treatments for root length. The interactions were significant at 1% P level for root length. Highest root length was recorded for NARC-2009 under T7 (4.8 cm) while lowest root length recorded for Sehar-06 (2.9 cm). Wheat genotypes varied considerably for root length at anthesis stage (**Table 10**). Genotype NARC-2009 accumulated highest root length (43.0 cm) whereas, genotype Sehar-06 accumulated lowest root length (35.3 cm). The percentage difference among both genotypes for number of seeds per spike was 18%. In the meanwhile, all the treatments varied noticeably for


**Table 9.** Shoot length for both genotypes at three leaf, anthesis and maturity. root length at anthesis stage. Maximum root length was recorded for T7 (54.8 cm) followed by T3 (51.7 cm) whereas, minimum root length was recorded for T1 (35.13 cm) at anthesis stage. There was 49% difference between T7 and T1 for root length. Similarly, the interactive effects were highly variable at anthesis stage. Highest root length (69.2 cm) was recorded for NARC-2009 under T7 while lowest root length (29.9 cm) was recorded for Sehar-06 under T7. Both the wheat genotypes varied considerably for root length at maturity stage (**Table 10**). NARC-2009 accumulated maximum root length (41.8 cm) while Sehar-06 accumulated minimum root length (34.3 cm). There was 18% difference among both the genotypes for root length accumulation. In the same way all the treatments varied significantly for root length. Highest root length was recorded was recorded for T7 (53.2 cm) followed by T3 (50.2 cm) and lowest root length was recorded for T5 (27.1 cm). There was 49% difference between T7 and T5. Similarly, the interactive effects were also significantly different at 1% P level for root length accumulation at maturity stage. Highest root length was recorded for NARC-2009 under T7 (67.3 cm) while lowest for Sehar-06 under T8 (29.1 cm). In the stress environment the length of roots increased to ensure proper supply of nutrients to the plant body. Phosphorus application enhanced root length to ensure better nutrient supply to the plant body. Our results were in accordance with Fahad and Bano [13] who stated that nutrient enhanced the crop stress tolerance hence help in root elongation. It would be advantageous if we select, screen or improve plants for higher capacity to adapt to mineral stresses. This approach is beneficial in developing countries like Pakistan where capital input resources are limited. Farmers in these countries require nutrient efficient crop cultivars which per

Mean 3.63B 4.25A 35.3B 43.0A 34.3B 41.8A

LSD for G 0.3783 5.8271 5.6636 LSD For T 0.7565 11.654 11.327 LSD for G × T 1.0699 16.482 16.019

**Table 10.** Root length for both genotypes at three leaf, anthesis and maturity.

**Treatments Three leaf Mean Anthesis Mean Maturity Mean G1 G2 G1 G2 G1 G2** T1 2.5d 3.49cd 3.17C 35.1b 35.1b 35.1B 34.2b 34.2b 34.2B T2 3.54b–d 3.71a–d 3.63BC 38.2b 39.3b 38.8B 37.2b 38.2b 37.7B T3 3.54b–d 3.97a–c 3.75BC 40.3b 63.0a 51.7A 39.2b 61.3a 50.2A T4 3.54b–d 4.44a–c 3.99AB 31b 32.0b 31.5B 30.1b 31.1b 30.6B T5 3.64b–d 4.57ab 4.11AB 29.9b 25.8b 27.9B 29.1b 25.1b 27.1B T6 3.44cd 4.44a–c 3.94AB 37.2b 41.3b 39.3B 36.2b 40.2b 38.2B T7 4.42a–c 4.77a 4.60A 40.3b 69.2a 54.8A 39.2b 67.3a 53.2A T8 4.02a–c 4.57ab 4.29AB 29.9b 38.2b 34.1B 29.1b 37.2b 33.1B

Effect of Phosphorus on Root Signaling of Wheat under Different Water Regimes

http://dx.doi.org/10.5772/intechopen.75806

15

form better or do something better than other cultivars when given a considerable amount

of mineral nutrient.



**Table 10.** Root length for both genotypes at three leaf, anthesis and maturity.

**Treatments**

**Three leaf**

**G1**

> T1

T2 T3 T4 T5 T6 T7 T8 Mean LSD for G LSD For T LSD for G × T

**Table 9.**

Shoot length for both genotypes at three leaf, anthesis and maturity.

2.3211

1.6412

0.8206

5.2833B

6.2867A

6.34bc

7.5433ab

6.9417AB

60.24a–c

54.37B 5.6734 11.347 16.047

63.754A

68.653ab

64.447AB

65.661a–c

59.262B

6.1844

12.369

17.492

69.492A

74.833ab

70.247AB

7.3967ab

8.8a

8.0983A

66.367a–c

71.64a

69.003A

72.338a–c

78.086a

75.212A

6.34bc

7.5433ab

6.9517AB

51.563cd

66.663a–c

59.113AB

56.201cd

72.664a–c

64.432AB

4.2267cd 5.2833b–d

6.2867bc

5.785BC

54.627b–d

68.653ab

61.64AB

59.54b–d

74.833ab

67.186AB

5.03cd

4.6283CD

53.093b–d

66.663a–c

59.878AB

57.87b–d

72.664a–c

65.267AB

4.2267cd 5.2833b–d

6.2867bc

5.785BC

53.093b–d

59.7a–c

56.397BC

57.87b–d

65.072a–c

61.471BC

5.03cd

4.6283CD

53.093b–d

55.72a–d

54.407BC

57.87b–d

60.734a–d

59.302BC

3.17d

3.7733d

3.4717D

42.883d

52.337cd

47.61C

46.742d

57.046cd

51.894C

14 Global Wheat Production

**G2**

**Mean**

**Anthesis**

**G1**

**G2**

**Mean**

**Maturity**

**G1**

**G2**

**Mean**

root length at anthesis stage. Maximum root length was recorded for T7 (54.8 cm) followed by T3 (51.7 cm) whereas, minimum root length was recorded for T1 (35.13 cm) at anthesis stage. There was 49% difference between T7 and T1 for root length. Similarly, the interactive effects were highly variable at anthesis stage. Highest root length (69.2 cm) was recorded for NARC-2009 under T7 while lowest root length (29.9 cm) was recorded for Sehar-06 under T7. Both the wheat genotypes varied considerably for root length at maturity stage (**Table 10**). NARC-2009 accumulated maximum root length (41.8 cm) while Sehar-06 accumulated minimum root length (34.3 cm). There was 18% difference among both the genotypes for root length accumulation. In the same way all the treatments varied significantly for root length. Highest root length was recorded was recorded for T7 (53.2 cm) followed by T3 (50.2 cm) and lowest root length was recorded for T5 (27.1 cm). There was 49% difference between T7 and T5. Similarly, the interactive effects were also significantly different at 1% P level for root length accumulation at maturity stage. Highest root length was recorded for NARC-2009 under T7 (67.3 cm) while lowest for Sehar-06 under T8 (29.1 cm). In the stress environment the length of roots increased to ensure proper supply of nutrients to the plant body. Phosphorus application enhanced root length to ensure better nutrient supply to the plant body. Our results were in accordance with Fahad and Bano [13] who stated that nutrient enhanced the crop stress tolerance hence help in root elongation. It would be advantageous if we select, screen or improve plants for higher capacity to adapt to mineral stresses. This approach is beneficial in developing countries like Pakistan where capital input resources are limited. Farmers in these countries require nutrient efficient crop cultivars which perform better or do something better than other cultivars when given a considerable amount of mineral nutrient.

#### *4.2.3. Shoot dry weight*

Both the genotypes differed considerably for shoot dry weight accumulation (**Table 11**). The results depicted that maximum shoot dry weight was accumulated by NARC-2009 (0.21 g) while minimum shoot fresh weight was accumulated by Sehar-06 (0.14 g) at three leaf stage. There was 32% variation among both the genotypes for shoot dry weight accumulation at three leaf stage. On the other hand, all the treatments exhibited significant difference for shoot dry weight at three leaf stage. Highest shoot dry weight was recorded for T7 (0.25 g) while lowest shoot dry weight was recorded by T4 (0.11 g). There was 57% difference among higher and lower treatments. In the same way, the interactive effects varied potentially. Highest shoot dry weight recorded for NARC-2009 (0.29 g) under T7 while lowest shoot dry weight was recorded for Sehar-06 under T4 (0.08 g). There was 61% difference among maximum and minimum shoot dry weights. Genotype NARC-2009 and Sehar-06 did not varied potentially for shoot dry weight at anthesis stage (**Table 11**). Whereas, all the treatments varied noticeably for shoot dry weight at anthesis stage. Maximum shoot dry was recorded for T7 (1.59 g) followed by other treatments except T4 which accumulated minimum shoot dry weight (1.28 g) at anthesis stage. There was 19% difference between T7 and T4 for shoot dry weight at anthesis. Similarly, the interactive effects were highly variable at anthesis stage. Highest shoot dry weight (1.66 g) was recorded for NARC-2009 under T7 while lowest shoot dry weight (1.23 g) was recorded for Sehar-06 under T4. There was 25% difference among highest and lowest shoot dry weight under all the treatments for both the genotypes. Both the genotypes did not differ considerably for shoot dry weight accumulation at maturity stage (**Table 11**). On the other hand, all the treatments exhibited significant difference for shoot dry weight at maturity stage. Maximum shoot dry weight was accumulated for T7 (2.55 g) while minimum shoot dry weight was recorded by T4 (2.06 g). There was 19% difference among higher and lower treatments. In the same way, the interactive effects varied considerably. Highest shoot dry weight was recorded for NARC-2009 (2.66 g) under T7 followed by all other treatments except Sehar-06 under T4 (1.97 g) fallowed by Sehar-06 under T5 (1.97 g). There was 26% difference among maximum and minimum shoot dry weights. Root signaling influence directly above ground biomass production. With the application of phosphorus roots were able to penetrate deep in the soil to provide better nutrients to the above ground parts. Our results were in accordance to Dewal and Pareek, [50] who stated that dry matter production increased by the addition of phosphorus. Similar results were also reported by Swarup and Yaduvanshi, [51] who concluded that fertilization of crop with phosphatic compounds resulted in enhanced

Effect of Phosphorus on Root Signaling of Wheat under Different Water Regimes

http://dx.doi.org/10.5772/intechopen.75806

17

Balanced plant nutrition encourages above and below ground plant growth development. Both the genotypes differed considerably for root dry weight at three leaf stage (**Table 12**). Genotype NARC-2009 accumulated maximum root dry weight (0.16 g) while Sehar-06 accumulated minimum root dry weight (0.11 g). There was 31% difference among genotypes for root dry weight at three leaf stage. All the treatments were statistically varied for root dry weight at three leaf stage. The highest root dry weight was recorded for treatment T7 (0.195 g) while, lowest root dry weight was recorded for T1 (0.08 g). In the same way, the interactive effects differed considerably for root dry weight under all the treatments for both genotypes at three leaf stage. Maximum root dry weight was accumulated by NARC-2009 under T7 (0.23 g) whereas, minimum root dry weight was accumulated by Sehar-06 under T1 (0.07 g). Both the genotypes did not varied considerably for root dry weight at anthesis stage (**Table 12**). On the other hand, all the treatments varied noticeably for root dry weight at anthesis stage. Maximum root dry was

**Treatments Three leaf Mean Anthesis Mean Maturity Mean G1 G2 G1 G2 G1 G2** T1 0.07c 0.09bc 0.08C 1.2ab 1.31ab 1.26AB 1.53ab 1.66ab 1.59AB T2 0.09bc 0.13a–c 0.11BC 1.32ab 1.45ab 1.39AB 1.68ab 1.83ab 1.76AB T3 0.11bc 0.16a–c 0.14ABC 1.2ab 1.31ab 1.25AB 1.52ab 1.66ab 1.59AB T4 0.09bc 0.13a–c 0.11BC 1.14b 1.24ab 1.19B 1.44b 1.57ab 1.51B T5 0.11bc 0.16a–c 0.14ABC 1.19b 1.29ab 1.24AB 1.50b 1.64ab 1.57AB T6 0.13a–c 0.19ab 0.17AB 1.21ab 1.32ab 1.27AB 1.54ab 1.68ab 1.61AB T7 0.16a–c 0.23a 0.19A 1.41ab 1.53a 1.47A 1.79ab 1.95a 1.87A T8 0.13a–c 0.19ab 0.16AB 1.32ab 1.45ab 1.39AB 1.68ab 1.83ab 1.76AB

Mean 0.12B 0.16A 1.25NS 1.37 1.58NS 1.73

0.1041 0.3449 0.4376

LSD for G 0.0368 0.122 0.1547 LSD For T 0.0736 0.2439 0.3095

**Table 12.** Root dry weight for both genotypes at three leaf, anthesis and maturity.

dry matter accumulation.

*4.2.4. Root dry weight*

LSD for G × T


**Table 11.** Shoot dry weight for both genotypes at three leaf, anthesis and maturity.

treatments. In the same way, the interactive effects varied considerably. Highest shoot dry weight was recorded for NARC-2009 (2.66 g) under T7 followed by all other treatments except Sehar-06 under T4 (1.97 g) fallowed by Sehar-06 under T5 (1.97 g). There was 26% difference among maximum and minimum shoot dry weights. Root signaling influence directly above ground biomass production. With the application of phosphorus roots were able to penetrate deep in the soil to provide better nutrients to the above ground parts. Our results were in accordance to Dewal and Pareek, [50] who stated that dry matter production increased by the addition of phosphorus. Similar results were also reported by Swarup and Yaduvanshi, [51] who concluded that fertilization of crop with phosphatic compounds resulted in enhanced dry matter accumulation.

#### *4.2.4. Root dry weight*

*4.2.3. Shoot dry weight*

16 Global Wheat Production

LSD for G × T

Both the genotypes differed considerably for shoot dry weight accumulation (**Table 11**). The results depicted that maximum shoot dry weight was accumulated by NARC-2009 (0.21 g) while minimum shoot fresh weight was accumulated by Sehar-06 (0.14 g) at three leaf stage. There was 32% variation among both the genotypes for shoot dry weight accumulation at three leaf stage. On the other hand, all the treatments exhibited significant difference for shoot dry weight at three leaf stage. Highest shoot dry weight was recorded for T7 (0.25 g) while lowest shoot dry weight was recorded by T4 (0.11 g). There was 57% difference among higher and lower treatments. In the same way, the interactive effects varied potentially. Highest shoot dry weight recorded for NARC-2009 (0.29 g) under T7 while lowest shoot dry weight was recorded for Sehar-06 under T4 (0.08 g). There was 61% difference among maximum and minimum shoot dry weights. Genotype NARC-2009 and Sehar-06 did not varied potentially for shoot dry weight at anthesis stage (**Table 11**). Whereas, all the treatments varied noticeably for shoot dry weight at anthesis stage. Maximum shoot dry was recorded for T7 (1.59 g) followed by other treatments except T4 which accumulated minimum shoot dry weight (1.28 g) at anthesis stage. There was 19% difference between T7 and T4 for shoot dry weight at anthesis. Similarly, the interactive effects were highly variable at anthesis stage. Highest shoot dry weight (1.66 g) was recorded for NARC-2009 under T7 while lowest shoot dry weight (1.23 g) was recorded for Sehar-06 under T4. There was 25% difference among highest and lowest shoot dry weight under all the treatments for both the genotypes. Both the genotypes did not differ considerably for shoot dry weight accumulation at maturity stage (**Table 11**). On the other hand, all the treatments exhibited significant difference for shoot dry weight at maturity stage. Maximum shoot dry weight was accumulated for T7 (2.55 g) while minimum shoot dry weight was recorded by T4 (2.06 g). There was 19% difference among higher and lower

**Treatments Three leaf Mean Anthesis Mean Maturity Mean G1 G2 G1 G2 G1 G2** T1 0.08c 0.13bc 0.11C 1.30ab 1.42ab 1.36AB 2.09ab 2.28ab 2.18AB T2 0.11c 0.17a–c 0.14BC 1.44ab 1.57ab 1.50AB 2.30ab 2.51ab 2.40AB T3 0.14bc 0.21a–c 0.18A–C 1.3ab 1.42ab 1.36AB 2.08ab 2.27ab 2.18AB T4 0.11c 0.17a–c 0.14BC 1.23b 1.34ab 1.29B 1.97b 2.15ab 2.06B T5 0.14bc 0.21a–c 0.18A–C 1.28b 1.40ab 1.34AB 2.06b 2.25ab 2.15AB T6 0.17a–c 0.25ab 0.21AB 1.31ab 1.43ab 1.37AB 2.10ab 2.29ab 2.19AB T7 0.20a–c 0.29a 0.25A 1.52ab 1.66a 1.59A 2.44ab 2.66a 2.55A T8 0.17a–c 0.25ab 0.21AB 1.44ab 1.57ab 1.50AB 2.30ab 2.51ab 2.40AB

Mean 0.14B 0.21A 1.35NS 1.48 2.16NS 2.37

0.1349 0.3736 0.5991

LSD for G 0.0477 0.1321 0.2118 LSD For T 0.0954 0.2642 0.4236

**Table 11.** Shoot dry weight for both genotypes at three leaf, anthesis and maturity.

Balanced plant nutrition encourages above and below ground plant growth development. Both the genotypes differed considerably for root dry weight at three leaf stage (**Table 12**). Genotype NARC-2009 accumulated maximum root dry weight (0.16 g) while Sehar-06 accumulated minimum root dry weight (0.11 g). There was 31% difference among genotypes for root dry weight at three leaf stage. All the treatments were statistically varied for root dry weight at three leaf stage. The highest root dry weight was recorded for treatment T7 (0.195 g) while, lowest root dry weight was recorded for T1 (0.08 g). In the same way, the interactive effects differed considerably for root dry weight under all the treatments for both genotypes at three leaf stage. Maximum root dry weight was accumulated by NARC-2009 under T7 (0.23 g) whereas, minimum root dry weight was accumulated by Sehar-06 under T1 (0.07 g). Both the genotypes did not varied considerably for root dry weight at anthesis stage (**Table 12**). On the other hand, all the treatments varied noticeably for root dry weight at anthesis stage. Maximum root dry was


**Table 12.** Root dry weight for both genotypes at three leaf, anthesis and maturity.

recorded for T7 (1.47 g) fallowed by other treatments except T4 which accumulated minimum root dry weight (1.18 g) at anthesis stage. There was 24% difference between T7 and T4 for root dry weight at anthesis. Similarly, the interactive effects were highly variable at anthesis stage for root dry weight at anthesis stage. Highest root dry weight (1.53 g) was recorded for NARC-2009 under T7 while lowest shoot dry weight (1.14 g) was recorded for Sehar-06 under T4. There was 25% difference among highest and lowest root dry weight under all the treatments for both the genotypes. Both the genotypes were not varied potentially for root dry weight at maturity (**Table 12**). In the meanwhile, all the treatments differed significantly for root dry weight at maturity stage. Highest root dry weight was calculated for T7 (1.86 g cm) followed by all other treatments while, lowest was calculated for T4 (1.51 g). There was 19% variation among highest and lowest treatments for root dry weight. Meanwhile, the interactive effects were highly significant at 1% P level for root dry weight. Highest root dry weight was recorded for NARC-2009 under T7 (1.94 g) while lowest for Sehar-06 under T4 (1.44 g).

was recorded for Sehar-06 under T6. There was 42% difference among highest and lowest root dry weight under all the treatments for both the genotypes. Both the wheat genotypes did not varied considerably for root to shoot ratio at anthesis stage (**Table 13**). In the meanwhile, all the treatments varied significantly for root to shoot ratio at anthesis stage. Highest root to shoot ratio was recorded for T3 (0.90) and lowest root to shoot ratio recorded for T5 (0.46). There was 48% difference between T3 and T5. Similarly, the interactive effects were also significantly different at 1% P level for root to shoot ratio at anthesis stage. Highest root to shoot ratio was recorded for NARC-2009 under T3 (1.05) followed by NARC-2009 under T7 (0.96) while lowest for NARC-2209 under T5 (0.37). There was 48% difference among highest and lowest root dry

Effect of Phosphorus on Root Signaling of Wheat under Different Water Regimes

http://dx.doi.org/10.5772/intechopen.75806

19

Both the genotypes were not different for root to shoot ratio at maturity stage (**Table 13**). In the meanwhile, all the treatments differed significantly for root to shoot ratio at maturity stage. Highest root to shoot ratio was calculated for T3 (0.81) followed by all other treatments while, lowest was calculated for T5 (0.41). There was 49% variation among highest and lowest treatments for root to shoot ratio at maturity stage. Meanwhile, the interactive effects were highly significant at 1% P level for root to shoot ratio. Highest root to shoot ratio was recorded for NARC-2009 under T3 (0.93) fallowed by NARC-2009 under T7 (0.85) while lowest for NARC-2209 under T5 (0.33). There was 64% difference among highest and lowest root dry weight under all the treatments for both the genotypes at maturity stage. Root architecture is a highly plastic and environmentally responsive trait that enables plants to counteract nutrient scarcities with different forging strategies [7]. Root-specific traits such as root system architecture, sensing of edaphic stress and root-to-shoot communication can be exploited to improve resource capture (water and nutrients) and plant development under resource-limited conditions [8].

**Treatments\genotypes Sehar-06 NARC-2009 Mean** T1 8.4ab 9.1ab 8.7AB T2 9.2ab 10.0ab 9.6AB T3 8.3ab 9.1ab 8.7AB T4 7.9b 8.6ab 8.2B T5 8.2b 8.9ab 8.6AB T6 8.4ab 9.2ab 8.8AB T7 9.8ab 10.7a 10.2A T8 9.2ab 10.0ab 9.6AB

Mean 8.7B 9.5A

LSD for G 0.7473 LSD for T 1.6947 LSD for G × T 2.3966

**Table 14.** Spike length for both genotypes at maturity.

weight under all the treatments for both the genotypes at anthesis stage.

#### *4.2.5. Root-shoot ratio*

Both the genotypes were non-significant for root to shoot ratio at three leaf stage (**Table 13**). Whereas, all the treatments varied noticeably for root to shoot ratio at three leaf stage. Maximum root to shoot ratio recorded for T1 (0.92) while minimum root to shoot ratio calculated for T6 (0.57) at three leaf stage. There was 38% difference between T1 and T6 for root to shoot ratio at three leaf stage. Similarly, the interactive effects were highly variable at three leaf stage for root to shoot ratio at three leaf stage. Highest root to shoot ratio (0.94) was recorded for NARC-2009 under T1 followed by Sehar-06 under T1 (0.90) while lowest root to shoot ratio (0.54 g)


**Table 13.** Root-shoot ratio for both genotypes at three leaf, anthesis and maturity.

was recorded for Sehar-06 under T6. There was 42% difference among highest and lowest root dry weight under all the treatments for both the genotypes. Both the wheat genotypes did not varied considerably for root to shoot ratio at anthesis stage (**Table 13**). In the meanwhile, all the treatments varied significantly for root to shoot ratio at anthesis stage. Highest root to shoot ratio was recorded for T3 (0.90) and lowest root to shoot ratio recorded for T5 (0.46). There was 48% difference between T3 and T5. Similarly, the interactive effects were also significantly different at 1% P level for root to shoot ratio at anthesis stage. Highest root to shoot ratio was recorded for NARC-2009 under T3 (1.05) followed by NARC-2009 under T7 (0.96) while lowest for NARC-2209 under T5 (0.37). There was 48% difference among highest and lowest root dry weight under all the treatments for both the genotypes at anthesis stage.

Both the genotypes were not different for root to shoot ratio at maturity stage (**Table 13**). In the meanwhile, all the treatments differed significantly for root to shoot ratio at maturity stage. Highest root to shoot ratio was calculated for T3 (0.81) followed by all other treatments while, lowest was calculated for T5 (0.41). There was 49% variation among highest and lowest treatments for root to shoot ratio at maturity stage. Meanwhile, the interactive effects were highly significant at 1% P level for root to shoot ratio. Highest root to shoot ratio was recorded for NARC-2009 under T3 (0.93) fallowed by NARC-2009 under T7 (0.85) while lowest for NARC-2209 under T5 (0.33). There was 64% difference among highest and lowest root dry weight under all the treatments for both the genotypes at maturity stage. Root architecture is a highly plastic and environmentally responsive trait that enables plants to counteract nutrient scarcities with different forging strategies [7]. Root-specific traits such as root system architecture, sensing of edaphic stress and root-to-shoot communication can be exploited to improve resource capture (water and nutrients) and plant development under resource-limited conditions [8].


**Table 14.** Spike length for both genotypes at maturity.

recorded for T7 (1.47 g) fallowed by other treatments except T4 which accumulated minimum root dry weight (1.18 g) at anthesis stage. There was 24% difference between T7 and T4 for root dry weight at anthesis. Similarly, the interactive effects were highly variable at anthesis stage for root dry weight at anthesis stage. Highest root dry weight (1.53 g) was recorded for NARC-2009 under T7 while lowest shoot dry weight (1.14 g) was recorded for Sehar-06 under T4. There was 25% difference among highest and lowest root dry weight under all the treatments for both the genotypes. Both the genotypes were not varied potentially for root dry weight at maturity (**Table 12**). In the meanwhile, all the treatments differed significantly for root dry weight at maturity stage. Highest root dry weight was calculated for T7 (1.86 g cm) followed by all other treatments while, lowest was calculated for T4 (1.51 g). There was 19% variation among highest and lowest treatments for root dry weight. Meanwhile, the interactive effects were highly significant at 1% P level for root dry weight. Highest root dry weight was recorded

Both the genotypes were non-significant for root to shoot ratio at three leaf stage (**Table 13**). Whereas, all the treatments varied noticeably for root to shoot ratio at three leaf stage. Maximum root to shoot ratio recorded for T1 (0.92) while minimum root to shoot ratio calculated for T6 (0.57) at three leaf stage. There was 38% difference between T1 and T6 for root to shoot ratio at three leaf stage. Similarly, the interactive effects were highly variable at three leaf stage for root to shoot ratio at three leaf stage. Highest root to shoot ratio (0.94) was recorded for NARC-2009 under T1 followed by Sehar-06 under T1 (0.90) while lowest root to shoot ratio (0.54 g)

**Treatments RSRT Mean RSRA Mean RSRM Mean G1 G2 G1 G2 G1 G2** T1 0.90a 0.95a 0.93A 0.82b 0.66c–e 0.74BC 0.73b 0.59c–e 0.66BC T2 0.84ab 0.76bc 0.79BC 0.72b–d 0.69cd 0.71BC 0.64b–d 0.63b–d 0.63BC T3 0.67c–f 0.65c–g 0.66DE 0.76bc 1.05a 0.91A 0.67bc 0.93a 0.81A T4 0.84ab 0.90a 0.87AB 0.58e–h 0.48hi 0.53D 0.52e–g 0.42gh 0.47D T5 0.69c–e 0.75b–d 0.72CD 0.55f–h 0.37i 0.46D 0.49fg 0.33h 0.41D T6 0.54g 0.60e–g 0.57F 0.72b–d 0.61d–f 0.67C 0.64b–d 0.55d–f 0.59C T7 0.59e–g 0.56fg 0.58EF 0.64d–g 0.96a 0.78B 0.54d–f 0.85a 0.69B T8 0.63d–g 0.62e–g 0.63EF 0.49gh 0.55e–h 0.52D 0.44fg 0.49e–g 0.47D

Mean 0.71NS 0.72 0.66NS 0.67 0.59NS 0.6

0.1204 0.116 0.1042

LSD for G 0.0426 0.041 0.0368 LSD For T 0.0852 0.082 0.0737

**Table 13.** Root-shoot ratio for both genotypes at three leaf, anthesis and maturity.

for NARC-2009 under T7 (1.94 g) while lowest for Sehar-06 under T4 (1.44 g).

*4.2.5. Root-shoot ratio*

18 Global Wheat Production

LSD for G × T

### *4.2.6. Spike length*

Spike length of the both wheat genotypes differed considerably due to their genetic characteristics (**Table 14**). The results illustrated that the higher spike length was recorded for the NARC-2009 (9.5 cm) against Sehar-06 (8.7 cm). The difference between both genotypes was 8%. While discussing about treatments, maximum spike length was recorded for T7 (10.2 cm), while the minimum spike length was noticed under T4 (8.2 cm). There was 14% difference among highest and lowest treatments. Similarly, the interactive effect was significant. Highest spike length was recorded for NARC-2009 under T7 (10.7 cm) while lowest spike length was observed for Sehar-06 under T4 (7.89 cm). There was 21% variation for spike length among highest and lowest interactions. Root signaling played a vital role in the development of the good source-sink relationship. Maximum spike length is produced as translocation of more photo-assimilates takes place efficiently from source to sink. Balanced application of P fertilizers and their availability might be another reason of spike length increment. Our findings were in accordance with Dewal and Pareek [50] and Memon [52] who reported increment in spike length with the addition of P fertilizers. Our results were also confirmed by the findings of Hussain [53] who reported increase in spike length due to P addition.

application of P fertilizers and enhanced availability as well as uptake of phosphorus through root signaling by plants. Another reason might be spike length which consumes available nutrient resources as well as temperature in more proficient way and accumulated photoassimilates efficiently. As P application and availability support growth and developmental process in plants through root signaling such as photosynthesis, energy storage, transfer, cell division as well as cell elongation so it also promotes spikelets initiation and finally increases number of spikelets per spike. Similar results were reported by Memon [52] who observed a significant increase in number of spikelets per spike by the application of P fertilizers through

Effect of Phosphorus on Root Signaling of Wheat under Different Water Regimes

http://dx.doi.org/10.5772/intechopen.75806

21

Both the genotypes varied potentially for number of grains per spike (**Table 16**). NARC-2009 exhibited maximum number of grains per spike (23.56) than Sehar-06 (21.45). There was 9% difference among both the genotypes for number of grains per spike. All the treatments showed significant difference for number of grains per spike. Highest number of grains per spike was recorded for T7 (26.99) while lowest number of grains per spike was recorded for T4 (20.07). In the same way, the interactive effect was also found significant. Maximum number of grains per spike was recorded for NARC-2009 under T7 (28.21) whereas, minimum number of grains per spike was recorded for Sehar-06 under T4 (19.21). Root signaling played a vital role in enhancing number of grains per spike. By applying phosphorus root signaling enhanced in the crop. Sufficient availability and the uptake of P facilitate the crop to grow more rapidly and it also enables the crop to capture more solar radiations and consequently more number of grains per spike produced. Insufficiency of P undersized the growth of stem as well as whole plant. However, the addition of P encourages the plant growth which results in increase in number of spikelets per spike due to better root signaling. With the increase in number of spikelets per spike, number of grains per spike also increased. The results of present study were in line with Ali et al. [54] and Dewal and Pareek [50] who observed the reduction in number of grains per

**Treatments/genotypes Sehar-06 NARC-2009 Mean** T1 20.32cd 21.81b–d 21.07BC T2 22.41a–d 24.42a–d 23.42A–C T3 20.27cd 22.09a–d 21.19BC T4 19.21d 20.93b–d 20.07C T5 20.06cd 21.87b–d 20.97BC T6 20.85b–d 22.33a–d 21.59BC T7 25.79a–c 28.21a 26.99A T8 22.66a–d 26.84ab 24.75AB

Mean 21.45B 23.56A

**Table 16.** Number of grains per spike for both genotypes at maturity.

LSD for G 2.1023 LSD for T 4.4173 LSD for G × T 6.267

enhanced root signaling.

*4.2.8. Number of grains per spike*

#### *4.2.7. Spikelets per spike*

Spikelets per spike of the both wheat genotypes varied noticeably due to their genetic characteristics (**Table 15**). The results depicted that the higher spikelets per spike was observed for the NARC-2009 (2.7) against Sehar-06 (2.5). The difference between both genotypes was 8%. As regards to treatments, maximum spike length was recorded for T7 (2.9), while the minimum spike length (2.4) was noticed under T4. There was 15% difference among highest and lowest treatments. Similarly, the interactive effect was significant. Highest spike length was recorded for NARC-2009 under T7 (3.1) while lowest spikelets per spike were observed for Sehar-06 under T4 (2.3). There was 22% variation for spikelets per spike among highest and lowest interactions. The variation in number of spikelets per spike might be due to balanced


**Table 15.** Spikelets per spike for both genotypes at maturity.

application of P fertilizers and enhanced availability as well as uptake of phosphorus through root signaling by plants. Another reason might be spike length which consumes available nutrient resources as well as temperature in more proficient way and accumulated photoassimilates efficiently. As P application and availability support growth and developmental process in plants through root signaling such as photosynthesis, energy storage, transfer, cell division as well as cell elongation so it also promotes spikelets initiation and finally increases number of spikelets per spike. Similar results were reported by Memon [52] who observed a significant increase in number of spikelets per spike by the application of P fertilizers through enhanced root signaling.
