Lavkesh varma.pptx Breeding for drought tolerance in maize

Breeding for drought tolerance in maize JV college M.Sc Agriculture genetic and plant breeding

1. Welcome

2. SEMINAR- TOPIC BREEDING FOR DROUGHT TOLERANCE IN MAIZE JANTA VEDIC COLLEGE , BARAUT BAGHPAT DEPARTMENT OF GENETICS & PLANT BREEDING Lavkesh Varma

3. Drought stress: - It is a period of shortage of rainfall or non-availability of the rainfall to the crop plants. More than 20% yield loss is through drought. Drought at seedling stage stop cell division and cause cessation of growth. Drought reduces the length and weight of shoot. Drought reduces the photosynthesis(Affects PS-1 and create reactive electron species and degrade chloroplast). Drought at critical stages (Tasseling and Silking ) cause severe yield loss. Breeding for drought tolerance in maize

4. Type of drought resistance Drought escape Drought avoidance Drought tolerance Drought escape Drought escape describes the situation where an drought susceptible variety performs well in a drought environment by avoiding the period of drought. Early maturity is an important attribute of drought escape.

5. Drought avoidance It is the ability of plants to maintain relatively high tissue- water potential despite a shortage of soil- moisture. Drought avoidance is performed by maintenance of turgor through roots grow deeper in the soil, stomatal control of transpiration and by reduction of water loss through reduced epidermal i.e. reduced surface by smaller and thicker leaves. Drought tolerance The plant will face the drought but it shows less effect on its yield through it is affected by the drought.

6. Maize: Irrigation profile: - Maize needs well distributed rainfall. The rainfall should be 500-750mm. Tasseling and silking stages (70th and 85th) are critical. Critical stage needs copious irrigation.

7. Varieties of maize for Drought tolerance PAC-745, BH-19, SAMPARN, PAC748, KMH-408710. YSC 354, CML470/CML472. PAC-740, C900MG, VIVEK HYBRID-9

8. Ways to improve yield in Maize Growing very high yielding varieties under stress conditions may give moderate yields. Followed by eliminating negative traits. Improving drought tolerant varieties recurrent selection.

9. Improvement of drought tolerance \ Finding drought tolerant traits and its mechanisms. These genes are multigenic and low frequency genes. The frequency is increased by recurrent selection.

10. Mechanism of drought tolerance May not flower and recover on watering. May close the stomata and reduce transpiration. Increased depth of roots. Short anthesis and silking interval. Degree of leaf rolling. Abscisic acid production. Amino acids like aspargine , proline production, glycine betaine production.

11. Breeding programs Conventional selection. Marker aided Recurrent selection- Asr-1 gene. Quantitative trait loci- checking gene presence in stress and non-stress conditions. Transgenic programs. Using secondary traits in breeding programmes.

12. Reference https://www.slideshare.net/THANKLORD/improving-drought-tolerance-in-maize

13. Thank you