Evaluation of Drought Tolerance Indices and Nitrogen Fertilization for Some Groundnut (Arachis Hypogaea L.) Genotypes

Abstract

Water is essential to maximize crop yield and quality. This natural resource has assumed huge importance, especially in the warmest areas, where drought and environmental degradation has affected agricultural production. In order to identify drought tolerance of some groundnut genotypes and to investigate the relationships between seed yield, quality and drought tolerance indices a study was made using 10 promising genotypes. The experiment was carried out during 2014-2017 and sowed under randomized block design with four replicates. It included three factors: two levels of irrigation (a1 – non - irrigated and a2 - irrigated), two levels of fertilization (b1 – non-fertilized and b2 - 100 active Nitrogen/ha) and genotype (C1-C10). Seed yield depending on the influence of the factor, varied from 535.95 Kg/ha (non-irrigated) to 2020.95 Kg/ha (irrigated); from 1055.30 Kg/ha (non-fertilized) to 1501 Kg/ha (fertilized) and from 1111.30 Kg/ha to 1388 Kg/ha depending on genotype. Same influence factors for protein content varied from 25.65% (irrigated) to 28.61% (non-irrigated); from 26.33% (non-fertilized) to 27.93% (fertilized) and from 25.59% to 28.52% depending on genotype. Stress susceptibility index (SSI) varied from 0.964 to 1.040; Stress Tolerance Index (STI) from 0.138 to 0.435; Mean Productivity (MP) from 883.5 to 1616.0; Geometric Mean Productivity (GMP) from 750.3 to 1332.7; Tolerance index (TOL) from 933.0 to 1844.0; Harmonic Mean (HM) from 637.2 to 1099.0; Yield Index (YI) 0.777 to 1.308 and Yield Stability Index (YSI) from 0.236 to 0.309. High values of SSI, STI, YI, DI, RDI and SSPI indicate drought tolerance and those variants present high stability.

Identification of Peanut Germplasm Tolerance to Salinity Stress

“…The accessions that were identified as tolerant based on their ability to form pods and seeds and withstand on the effects of salinity can be employed and integrated in peanut breeding for salinity tolerance. Moreover, genotypes with potential yield under normal condition also have potential tolerance in stress condition because it has a positive correlation with the yield under stress (Paula et al 2019). On other hand, the ratio of Na-root/Na-shoot will be the new selection indicator of peanut tolerance to salinity stress.…”