Effect of stalk damage on growth and yield of certain maize cultivars by the maize stalk borer Chilo partellus

Increasing soil salinity due to global warming severely restricts crop growth and yield. To select and recommend salt-tolerant cultivars, extensive genotypic screening and examination of plants’ morpho-physiological responses to salt stress are required. In this study, 18 prescreened maize hybrid cultivars were examined at the early growth stage under a hydroponic system using multivariate analysis to demonstrate the genotypic and phenotypic variations of the selected cultivars under salt stress. The seedlings of all maize cultivars were evaluated with two salt levels: control (without NaCl) and salt stress (12 dS m−1 simulated with NaCl) for 28 d. A total of 18 morpho-physiological and ion accumulation traits were dissected using multivariate analysis, and salt tolerance index (STI) values of the examined traits were evaluated for grouping of cultivars into salt-tolerant and -sensitive groups. Salt stress significantly declined all measured traits except root–shoot ratio (RSR), while the cultivars responded differently. The cultivars were grouped into three clusters and the cultivars in Cluster-1 such as Prabhat, UniGreen NK41, Bisco 51, UniGreen UB100, Bharati 981 and Star Beej 7Star exhibited salt tolerance to a greater extent, accounting for higher STI in comparison to other cultivars grouped in Cluster-2 and Cluster-3. The high heritability (h2bs, >60%) and genetic advance (GAM, >20%) were recorded in 13 measured traits, indicating considerable genetic variations present in these traits. Therefore, using multivariate analysis based on the measured traits, six hybrid maize cultivars were selected as salt-tolerant and some traits such as Total Fresh Weight (TFW), Total Dry Weight (TDW), Total Na+, Total K+ contents and K+–Na+ Ratio could be effectively used for the selection criteria evaluating salt-tolerant maize genotypes at the early seedling stage.

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Effect of Sowing Dates and Maize Cultivars in Growth and Yield of Maize along with their Agro-Climatic Indices in Nawalparasi, Nepal

Journal of AgriSearch ◽

10.21921/jas.v3i1.4106 ◽

2016 ◽

Vol 3 (1) ◽

Cited By ~ 1

Author(s):

UMESH SHRESTHA ◽

LAL PRASAD AMGAIN ◽

TIKA BAHADUR KARKI ◽

KHEM RAJ DAHAL ◽

JIBAN SHRESTHA

Keyword(s):

Grain Yield ◽

Sowing Date ◽

Growth And Yield ◽

Phenological Stages ◽

Climatic Indices ◽

Maize Cultivars ◽

Sowing Dates ◽

Use Efficiency ◽

Research Period ◽

Late Sowing

A field experiment on different maize cultivars planted at different sowing dates were accomplished at Kawasoti-5, Nawalparasi during spring season of 2013 to find suitable sowing date and maize cultivar for the location. Along with this, effect of sowing dates and maize cultivars on different agro-climatic indices were also calculated using formulas. Result showed that RML- 4/RML-17 produced higher kernel rows ear-1 (13.77), kernel per row (30.42) and test weight (244.9 g). Significantly higher grain yield was also found for RML-4/RML-17 (6.03 tha-1) compared to Poshilo makai-1 (4.73 t ha-1), Arun-2 (3.55 t ha-1) and Local (2.92 t ha-1). Earlier sowing date (7th April) produced higher kernel row-1 (27.97), kernel rows ear-1 (12.89) and 1000 grain weight (230 g). Significantly higher grain yield (5.13t ha-1) was obtained in earlier sowing date (7th April). Although the mean ambient temperature during research period was increasing with delayed sowing, days to attain different phenological stages decreased with late sowing. The statistically similar GDD was recorded for different sowing dates and higher PTI values were noticed with delay in planting. Similarly, heat use efficiency (HUE) was found higher in early sowing date. Arun-2 had small reduction in HUE so, it can be considered stable and best cultivar among the tested cultivars.

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