Title & Method: Evaluation of Rice Genotypes and Mutants for Drought Tolerance

Evaluation of Rice Genotypes and Mutants for Drought Tolerance

_Dr. PB Kale (Date of draft for proposal; April 1, 2024)

SN	Expt.	Em(IM)blem	MapLocat(ions)	Address(s)	Title / Material and Method	Field Data	Cataloging	InfoBase Status
1	Expt 1: Evaluation of Rice Genotypes and Mutants for Drought Tolerance		https://maps.app.goo.gl/ZSP8e7y6iuHNrnRc8	VNGCAB-KVK Field area, Yavatmal Key Words: Rice, Drought, Rice	https://krishiprabha.blogspot.com/2025/01/evaluation-of-rice-genotypes-and.html	IR data	NO	YES
						Spectral signatures
						Phenomics data
						Genomics Data
						General articles

1. Selection of Plant Material

• Identify and procure a diverse set of rice genotypes and mutants with varying genetic backgrounds.
• Include drought-tolerant controls and sensitive checks for comparison.

2. Experimental Site Preparation

• Select well-defined experimental plots at the VNGCAB campus with controlled irrigation systems.
• Divide plots into two treatments:
• Well-Watered Condition (WW): Regular irrigation to maintain field capacity.
• Drought-Stressed Condition (DS): Water supply withheld at critical growth stages.

3. Experimental Design

• Use a Randomized Complete Block Design (RCBD) with three replicates for each genotype.
• Plot size: 5 rows per genotype, 3 meters long with 20 cm row spacing.

4. Sowing

• Date of sowing: June 15, 2024 (adjusted for monsoon onset in the region).
• Sow seeds manually, ensuring uniform spacing.

5. Management Practices

• Apply uniform fertilizers based on local recommendations: nitrogen, phosphorus, and potassium (N:P:K).
• Manage weeds manually or chemically as needed.
• Monitor pest and disease outbreaks and apply treatments uniformly across treatments.

6. Imposition of Drought Stress

• Withhold irrigation during:
• Vegetative Stage: 30-45 days after sowing.
• Reproductive Stage: Booting to flowering stage.
• Monitor soil moisture using tensiometers or soil moisture sensors.

7. Data Collection

• Morphological Parameters:
• Plant height, leaf area, tiller number, and biomass at harvest.
• Physiological Parameters:
• Relative water content (RWC), chlorophyll content (SPAD readings), and canopy temperature.
• Yield Parameters:
• Number of panicles per plant, grains per panicle, grain weight, and total yield.
• Root Traits:
• Root length, volume, and biomass (from a subset of plants).
• Molecular Analysis:
• Collect leaf samples for expression analysis of drought-responsive genes.

8. Statistical Analysis

• Analyze data using ANOVA to determine significant differences among genotypes under both treatments.
• Calculate drought tolerance indices, such as stress tolerance index (STI) and yield stability index (YSI).

9. Harvesting

• Harvest date: January 10-15, 2025.
• Thresh and weigh grains separately for each plot to calculate yield per hectare.

Expected Outcomes

1. Identifying drought-tolerant rice genotypes and mutants with superior yield and physiological performance under stress.
2. Insights into key morphological and physiological traits contributing to drought tolerance.
3. Establishment of molecular markers linked to drought tolerance for future breeding programs.
4. A ranked list of genotypes for use in breeding and cultivation under drought-prone environments.