**6. Impact of boron on seed germination and seed protein concentration**

Post harvested seeds of all crops received boron inadequate nourishment were reduced in size and showed poor rate of germination (**Figure 2**). Seed germination was found to be retarded 37%, 36% and 43% in soyabean, mustard and linseed respectively. All the storage protein fractions- albumins, globulins, glutelins and prolamins were decreased in seeds of boron inadequate supplied plants as compared to plants supplied with appropriate amount of boron. In soyabean and mustard prolamins was found to be marked reduced as compared to other protein fractions

**183**

**7. Conclusion**

**Figure 2.**

and 39% respectively) (**Figure 2**).

*Impact of Inadequate Concentration of Boron in Seed Storage Proteins Content in Oilseed Crops*

and globulins (in mustard) and glutelins (in soyabean) are least effective. In linseed seeds albumins were found to be decreased more than other fractions and glutelins were least decreased. In soyabean seeds decrease in prolamins and soluble proteins (≈52% and 66% respectively) were found to be more than albumins, globulins and glutelins (≈45%, 40% and 38% respectively). In mustard seeds also decrease in prolamins and soluble proteins (≈52% and 69% respectively) were found to be more than albumins, globulins and glutelins (≈26%, 23% and 29% respectively). In linseed seeds decrease in glutelins, prolamins and soluble proteins (≈20%, 35 and 14% respectively) were found to be less than albumins and globulins and (≈44%

*Impact of boron on seed germination rate and seed storage protein concentration.*

Inadequate boron nourishment may be a major factor responsible for low seed yield and quality of oil yielding crops widely cultivated on low boron soils world

*DOI: http://dx.doi.org/10.5772/intechopen.95873*

*Impact of Inadequate Concentration of Boron in Seed Storage Proteins Content in Oilseed Crops DOI: http://dx.doi.org/10.5772/intechopen.95873*

**Figure 2.**

*Grain and Seed Proteins Functionality*

kD prolamins at the mRNA and protein levels.

**5.3 Prolamins**

**5.4 Glutelins**

globulin might have a crucial role in a transcriptional mechanism and in the de novo

About 20% -30% seed protein is comprised of prolamins. Multigerne family of 34 gene copies having relative molecular weights −10, 13, and 16 kD encoding the prolamin proteins. Among them the 13 kD molecular weight gene family comprises the major group. Further, on the basis of abundance of cysteine residues the 13 kD prolamins are classified in class I, II, or III, [56, 57]. Prolamins are the main storage proteins in the endosperm of all cereal grains. These proteins are basically rich in proline and amide nitrogen which is derivative of glutamine. The prolamins contains variable molecular masses ranging from approx 10 000 to 100 000. Miflin et al. [58], on the basis of amino acid sequencing, classified the prolamins into three groups namely S-rich, S-poor, and high molecular weight (HMW) prolamins. Among them S-rich prolamins are found to be about 80 to 90% of the total prolamin fractions consisting of monomeric and polymeric components with intrachain and interchain disulfide bonds respectively. The most abundant prolamin group among rice storage proteins is 13 kD prolamins that is indigestible in nature (Hyun-Jung [59]). Kim et al. [59] have generated transgenic rice plants (13 kD pro-RNAi) consisting of RNAi that are constructing against 13 kD prolamins. They reported in their results that 28% increase in the level of lysine, and abnormal formation of PB-I (protein bodies) in the transgenic grains might be due to the reduction in 13

Glutelins are the member of the class of prolamin proteins. The seed endosperm

of the grass family is mostly enriched with glutelin proteins. Gluten is the main component of the glutelin protein. Zhao et al. [60] established that about 70–80% glutelins are present mostly in rice. They also reported that glutelins are homologous to 11-12S globulin proteins of leguminous family. Wakasa *et al.*, [61] explained that the pre-proglutelins are the initial precursor of glutelins and due to hydrophobic interactions in the lumen of the rough endoplasmic reticulum they form homotrimers and heterotrimers. [62] reported the 15 glutelin genes in the rice genome, and classified them on the basis of their amino acid sequences into four groups- Glu A, Glu B, Glu C, and Glu D. Glu A consists of three members Glu A1, Glu A 2 and Glu A 3 and Glu B have four members Glu B1, Glu B2 Glu B3 Glu B4. Takahashi *et al*., [63] demonstrated the localization pattern of five subtypes of the glutelin protein in rice grains with the help of glutelin-subtype specific antibodies. They reported that the localization of GluA was strongly in the outer region of the endosperm, including the subaleurone layer, and that of GluC was localized throughout the endosperm.

**6. Impact of boron on seed germination and seed protein concentration**

Post harvested seeds of all crops received boron inadequate nourishment were reduced in size and showed poor rate of germination (**Figure 2**). Seed germination was found to be retarded 37%, 36% and 43% in soyabean, mustard and linseed respectively. All the storage protein fractions- albumins, globulins, glutelins and prolamins were decreased in seeds of boron inadequate supplied plants as compared to plants supplied with appropriate amount of boron. In soyabean and mustard prolamins was found to be marked reduced as compared to other protein fractions

protein maturation process of storage proteins in the rice endosperm.

**182**

and globulins (in mustard) and glutelins (in soyabean) are least effective. In linseed seeds albumins were found to be decreased more than other fractions and glutelins were least decreased. In soyabean seeds decrease in prolamins and soluble proteins (≈52% and 66% respectively) were found to be more than albumins, globulins and glutelins (≈45%, 40% and 38% respectively). In mustard seeds also decrease in prolamins and soluble proteins (≈52% and 69% respectively) were found to be more than albumins, globulins and glutelins (≈26%, 23% and 29% respectively). In linseed seeds decrease in glutelins, prolamins and soluble proteins (≈20%, 35 and 14% respectively) were found to be less than albumins and globulins and (≈44% and 39% respectively) (**Figure 2**).

#### **7. Conclusion**

Inadequate boron nourishment may be a major factor responsible for low seed yield and quality of oil yielding crops widely cultivated on low boron soils world

over. Plants receiving inappropriate amount of boron nutrition showed decrease in all protein fractions. This might be due to increased activity of ribonuclease which disturbed the protein synthesis mechanism via influencing the RNA content of a cell. An increased ribonuclease activity in various crops under boron stressed condition was earlier observed by many workers [64, 65]. The observation made on the basis of results obtained in the present study suggested the role of boron in protein metabolism of seeds and that optimum concentration of boron is required for the appropriate synthesis of protein. Deformed seed structure and poor storage capacity for reserves might be the cause poor rate of seed germination. It is hoped that the information generated on the basis of this study will add to the information regarding the role of boron in seed protein reserve and quality improvement of seeds.
