Inter-Relationships Between Yield And Yield Attributes Of Potato Grown Under Supra-Optimal Ambient Temperatures

Abstract

Forty eight potato genotypes were evaluated in Saminaka (Lat. 10 0 27'N and Long 4 0 E, Mean Min. Temp 25 o C, Mean Max Temp 31.5 o C) during the rainy season of 1999 and 2000 to determine the inter-relationship between yield and some important agronomic traits in the potato grown under high ambient temperatures. The genotypes were laid out in a randomized complete block design with three replications. The genotypes exhibited highly significant variability (P<0.01) for all traits assessed. Tuber yield was positively associated with number of stems/plant (r = 0.246, P<0.05); plant height (r = 0.206, P<0.05); and number of leaves/plant (r = 0.237, P<0.05). Both the correlation and regression of yield on days to tuber initiation and days to maturity were negative and significant. This suggests that earliness in tuber initiation and maturity led to increased yield under supra optimal temperature probably due to reduced period of exposure to heat stress. Number of tubers per plant (R 2 = 0.383) and average tuber weight per plant (R 2 = 0.125) had the highest coefficients of determination of yield and by far the highest direct effects on yield (87.5% and 66.9%respectively) when compared to other attributes suggesting that they were the major contributors to yield under supra-optimal temperature conditions and may be relied upon in selecting for improved yield under such conditions.

Yield and yield component association of some capsicum genotypes

“…Combine analysis of variance showed high significant differences at P = 0.05 among the investigated capsicum genotypes considering all the evaluated yield components except days to 50% flowering and leaf area. High significant differences at P = 0.05 in plant characters within a population suggests the existence of sufficient variability upon which selection for improvement in these characters can be based (Amadi et al, 2008). The mean performances of the genotypes shows a clear indication of agronomic superiority of genotypes over others such as Tabasco pepper(Capsicum frutescens) with fruit yield of 2,426.6kg/ha and Bird pepper(Capsicum annuum) with yield of 2,239.9 kg/ha.…”

Stochastic Frontier Analysis for Potatoes in Egypt and Spain تحلیل استوکاستک للبطاطس فی مصر وإسبانیا

“…Potatoes are a major crop in Egypt and contribute immensely to human nutrition and food security (Karim, et al, 2010). The weather conditions during growing seasons and farm management are considered one of the most important constrains on the ability to increase production (Amadi, et al, 2009). There are three major cultivation seasons for potato in Egypt; Summer season cultivated during December and January, Nili season cultivated during late September and early October and winter season cultivated during late October and early November.…”