Evaluation of drought tolerance in different growth stages of maize (Zea mays L.) inbred lines using tolerance indices

Abstract

In order to find the best drought tolerant inbred lines, experiment was performed at the Agricultural College of Islamic Azad University, Shoushtar Branch, Iran during 2010. Experiment treatments were compared in a split-plot design by a randomized complete block design with 3 replications. Main factors included non-stress, drought stress in 6 to 7 leaves (vegetative) stage, drought stress in pollination stage and drought stress in grain filling stage. Sub factors were 7 inbred lines. Five stress tolerance indices, including mean productivity (MP), stress tolerance (TOL), stress susceptibility (SSI), stress tolerance index (STI) and geometric mean productivity (GMP) were used in this study. Drought stress in grain filling stage had the minimum grain yield that showed severe effects of drought stress at this stage of growth. Data analysis revealed that the MP, GMP and STI indices were the more accurate criteria for selection of drought tolerant and high yielding inbred lines. The positive and significant correlation of STI and grain yield under all conditions revealed that this index is more applicable and efficient for selection of parental inbred lines in producing hybrids tolerant to drought in vegetative, pollination and grain filling stages and high yielding under non-stress and stress conditions. Based on the STI, GMP and MP indices, K166B proved to be the most drought tolerant line. Biplot analysis allowed us to distinguish groups of tolerant and sensitive inbred lines. Based on the results of this study, the inbred line K166B can be recommended in future breeding programs for production of drought tolerant hybrids.

Metabolite profiles of maize leaves in drought, heat and combined stress field trials reveal the relationship between metabolism and grain yield

“…The negative effect of DS on maize yield is especially acute during the reproductive stage between tassel emergence and early grain filling (Grant et al, 1989), when it is believed to induce premature seed desiccation and to limit grain filling. Grain is more susceptible to DS than vegetative tissues; therefore, the prediction of grain yield from the physiological parameter of leaves is a challenge (Sangoi and Salvador, 1998;Khodarahmpour and Hamidi, 2011). Nevertheless, maize yield is dependent on both the assimilate supply to the kernel (source) and the potential of the kernel to accommodate this assimilate (sink potential; Jones and Simmons, 1983).…”

Corn root morphoanatomy at different development stages and yield under water stress

“…At the flowering period (VT), in which grain yield potential is determined, drought reduces the number of grains, leading to pollen desiccation, and, therefore, to an increase in the anthesis-silking interval and in early leaf senescence (Araus et al, 2012). Finally, during the grain filling period (R3), water deficit reduces the supply of assimilates at the source, leading to losses in grain weight (Khodarahmpour & Hamidi, 2011).…”

“…Therefore, major advances in understanding how corn plants respond to damages caused by drought have been based on evaluations performed on a single phenological stage (Khodarahmpour & Hamidi, 2011;Ge et al, 2012;Lavinsky et al, 2015), and little is known about corn responses to the cumulative effect of drought throughout its cycle, i.e., in more than one development stage.…”

Pima Cotton (Gossypium Barbadense L.) Lines Assessment for Drought Tolerance in Uzbekistan

“…The biplot diagram exhibited that drought indices MP, GMP, STI, MRP, REI, and YI, were the best indices in selecting the inbred line T-450 as a drought-tolerant genotype, with stable high seed yield under both conditions (Figure 1). The study presents the efficiency of PCA for adequate separation of inbred lines to drought tolerance indices, which was also confirmed in different species, i.e., maize (Khodarahmpour and Hamidi, 2011), sunflower (Ghaffari et al, 2012), wheat , grass pea (Basaran et al, 2012), and rice (Rahimi et al, 2013, Marcelo et al, 2017, Aminpanah et al, 2018. Except for DI, GM, SNPI under non-stress and SSI and GM under drought stress conditions, other indices have shown the highest correlation with seed cotton yield indicating more suitability of these indices for selection of resistant cotton inbred lines.…”