Supporting Physiological Trait for Indirect Selection for Grain Yield in Drought-Stressed Popcorn

Area of Science:

• Agronomy
• Plant Breeding
• Genetics

Background:

• Drought tolerance is crucial for popcorn (Zea mays everta) production, impacting grain yield and popping expansion.
• Identifying predictive traits aids in developing drought-resilient popcorn varieties.

Purpose of the Study:

• To identify morphological and leaf greenness traits that predict grain yield (GY) and popping expansion (PE) in popcorn under drought conditions.
• To evaluate the efficacy of multiple regression models in selecting superior popcorn lines for drought tolerance.

Main Methods:

• Assessed 20 popcorn lines under well-watered (WW) and water stress (WS) conditions.
• Measured morpho-agronomic traits (e.g., 100-grain weight, prolificacy) and leaf greenness (SPAD, NDVI).
• Utilized multiple regression to model relationships between traits and GY/PE.

Main Results:

• Water restriction significantly reduced GY (55%) and PE (28%).
• Morpho-agronomic traits like 100-grain weight and prolificacy were notably reduced under WS.
• SPAD index and tassel length were identified as indirect predictors for GY, while prolificacy strongly correlated with PE under WS.

Conclusions:

• Multiple regression is effective for identifying traits predictive of popcorn yield and quality under drought.
• Selected traits, including SPAD, tassel length, and prolificacy, can be utilized for indirect selection in breeding programs to enhance drought tolerance.