Effects of water stress on the rooting, nodulation potentials and growth of cowpea (<i>Vigna unguiculata</i> (l) walp)

Abstract

Rooting, nodulation and growth ability of cowpea growing under limited water supply was investigated at the Teaching and Research Farm of the Imo State University, Owerri, Nigeria. The experiment was conducted in plastic buckets arranged in a completely Randomized Design with three replications, and treatments represented as 500ml, 1000ml, and 1500ml of water, respectively. Control treatment was represented by cowpea plants that grown with rain-fed water. The 500ml and 1000ml of water were applied two times a week to the receiving cowpea plants while the 1500ml was applied daily to the receiving cowpea. Data were collected on the number of nodules/plant, root length/plant (cm) measured at 2 and 4 wks after planting (WAP) respectively, number of leaves/plant, number of branches/plant and seed yield (kg/ha) collected data were subjected to analysis of variance at the 5% level of significance. Results showed that cowpea plants that received 500ml of water produced mean nodule of 6.0 which was significantly (p<0.05) from the mean nodule of 13.2 produced by cowpea plant that grew under rain-fed condition. Cowpea plants that received 500 and 1000ml of water produced mean roots length of 9.8cm and 19.5cm at both 2 weeks and 4 weeks after planting, respectively, which were significantly (p<0.05) longer than 5.2cm and 13.4cm mean roots length in the control, at 2 and 4 WAP. Cowpeas that received 500ml of water produced mean plant height of 117cm and number of branches of 1.0 which were significantly different (p<0.05) from the mean plants height of 47cm and number of branches of 4.1 in the control plants. Seed yield was significantly (p<0.05) higher in the control plants than in the plants that received 500 and 1000ml of water, respectively. It was concluded that root characteristics nodulation potential and seed yield of cowpea were affected by the limiting water supply. Optimal water supply for cowpeas growing in pots should therefore be studied for better irrigation management and optimal performance of cowpea.

Water use efficiency and yield of cowpea and nutrient loss in lysimeter experiment under varying water table depth, irrigation schedules and irrigation method

“…Reduction in soil moisture availability within the root zone reduced root nodulation of the crop indicating that water is an essential input for root nodulation and shortage of which reduced formation of nodules. This finding is inconformity with the observations of Serraj (2003) and Onuh and Donald (2009). There was a significant difference in the number of pods per plant under the three irrigation schedules.…”

“…However, it is susceptible to moisture stress especially at flowering and pod filling stages (Aboamera, 2010). Moisture stress also markedly retards root hair and nodule growth and nitrogen fixation (Onuh and Donald, 2009). Although the crop responds positively to irrigation, it grows well under dry land conditions.…”

Study of Productivity and Economic Evaluation of Intercropping Cowpea With Maize Under Three Irrigation Water Levels and Their Response to Insect Infestation and Viral Infection

“…All parts of the plant used as food are nutritious providing protein and vitamins, immature pods and peas are used as vegetables while several snacks and main dishes are prepared from the grains (Islam et al, 2006). However, moisture stress markedly retards root hair and nodule growth and nitrogen (N) fixation (Onuh and Donald, 2009). In Egypt, cowpea is promising double purpose forage and seed crop for its green canopy or using it in animal diets as dry seeds, as well as it is a primary source of plant protein for humans and animals in the summer season (HamdAlla et al, 2014).…”

Response of Summer Cowpea to Growth, Yield and Water Use Efficiency under different Irrigation and Nutrient Management in Lower Indo-Gangetic Plains

“…Among the various factors of production, adequate soil moisture availability can lead to greater yield. The crop is susceptible to water stress especially at flowering and pod filling stages and markedly inhibits root hair, nodule growth and biological nitrogen fixation (Onuh and Donald, 2009; Aboamera, 2010) (13,2) . Water stress affects the whole process of growth of all organs, metabolism and photosynthesis rate of plant resulting into low production (Zimmermann et al, 1988) (20) .…”