**8. Time tested tips for breeding for drought across crops**

A deluge of information and knowledge has been generated over time. Considerable invest‐ ment has been made by the international community and funding agencies. The collective intelligence can be summarized as under.


if stage specific drought resistance is built into a variety and should drought occur at some other stage. Breeding effort would be futile.

**9.** Need to select for combination of stresses that challenge the crop in the farmers' field rather than only drought resistance. This will ensure longer survival of the variety in the farmers' field [22].

**Figure 4.** Borrowed from Kell DB, Annals of Botany, pp 1-12.[23]

In conclusion, breeding for drought resistance can do only as much as develop a genotype that can tolerate to moisture stress and respond to incremental water inputs should that be possible in the given habitat. The final answer to maximizing productivity comes from an integrated approach where genotype, agronomy, management, economics and policy come together to maximize the water productivity, the key limiting natural resource. Water is not equitably distributed in the world and the scarcity of water is assuming ominous dimensions (Figure 3).

A deluge of information and knowledge has been generated over time. Considerable invest‐ ment has been made by the international community and funding agencies. The collective

**1.** Screen parents and segregants in a habit that most closely represent/ resemble the target

**2.** Repeat phenotyping over years and seasons so that maximum possible variations in the

**3.** Impose selection starting from early generation (not F2) in well-watered and stress conditions. This will ensure selection for potential productivity (should stress not occur in the farmers' fields) and still maximize productivity under stress (should it occur). This will ensure that the farmer is likely to harness the full potential of every incremental drop

**4.** Quantify the water that is received by the field during the experimental period. Input of water could come in the form of rainfall or surface irrigation. It would be ideal to also document the evapotranspiration from the field. This will help budget water at the level of each genotype/segregant/plot. With such data, water productivity could be computed

**5.** While stability of the drought variety is highly desirable, local adaptability is also very important. A genotype may manifest low stability and may be use-full for the particular

**6.** High yield under favorable conditions (moisture regimes) can be combined with the high degree of drought resistance. Thus, traits associated with drought need not be a penalty

**7.** Selection for root and shoot morphology can be judiciously combined in ongoing breeding

**8.** Instead of incorporating growth stage specific drought resistance (vegetative stage drought resistance, reproductive stage drought resistance etc.) it is more appropriate to make any and every growth stage of the crop drought resistant as the timing of occurrence of drought, if at all in the farmers' field is unpredictable. It would be counterproductive

**8. Time tested tips for breeding for drought across crops**

intelligence can be summarized as under.

environmental conditions are represented.

of water above the threshold called drought.

to the plant under well-watered condition.

program while selecting for resistance to diseases and pests.

for each segregant, genotype.

habitat.

population of habitats.

162 Plant Breeding from Laboratories to Fields

This calls for ushering a blue revolution [2, 23], the water equivalent of green revolution, where it is envisaged that the water productivity in agriculture is addressed along with equity of water distribution between urban aspirations and rural needs. Finally [24] proposes that roots do much more than supply water to plants, they capture carbon and a well-endowed root system is not only important to the plant but also as a means to mitigate climate change, by trapping carbon in the form of increased microbial activity and dry matter accumulations. Thus, roots not only provide anchor, water, nutrients but also contribute to carbon sequestra‐ tion and one of the means to mitigate global warming.

Finally, using all shoot and root characters of the plant, be it morphological, physiological, biochemical, phenological, anatomical or responses to environment would provide more opportunities for enhancing drought resistance of the crop. The characters of the plant have to be matched with the appropriate agronomic practices to maximize the expression of the traits. This is a holistic approach to plant breeding for drought resistance and also referred to as 'whole-plant breeding'.
