Effect of Different Water Harvesting Techniques on Growth and Yield of Pearl millet (Pennisetum glaucum) Intercropped with Cowpea (Vigina sinensis) in North Darfur

Abstract

Two field experiments were conducted for two consecutive rainy seasons of 2011/12 and 2012/13 at Umhojar Village, Kabkabiya Locality- North Darfur State, Sudan to study the effect of different rainwater harvesting techniques on growth and yield of pearl millet intercropped with cowpea. The area lies on sandy clay loam soil at Latitude 13o. 04" N and Longitude 24o.08" E,). Split plot design with four replicates was used in which five water harvesting techniques viz.; W1 (Terracing system), W2 (V- shape micro- catchments), W3 (Contour bunds), W4 (Trapezoidal bunds method), W5 (rain fall control) were assigned into the sub plots whereas millet (Pennisetum glaucum) intercropped with cowpea (Vigina sinensis) were assigned into the main plots in addition to pure millet in monoculture. The growth parameters measured were plant height, number of leaves/plant, leaf area index, stem- diameter and plant density, taken three times at seedling, flowering and maturity stage in addition to days to 50% flowering, days to maturity and straw yields. Yield parameters measured were; panicle length (cm), yield (kg/ha); and 1000- seed weight (g) of millet. For Cowpea the parameters measured were; number of flowers per raceme, number of pods per flower, number of seed per pod, 100- seeds weight (g) and total yield (kg/ha). In addition, soil moisture content at different growth stages (seedling, flowering and maturity) and at different depths (0-20cm, 20-40cm and 40- 60cm) was also measured. Yield quality (nutritive value) in terms of protein content, fiber content and phosphorus content, ash (minerals) for both cowpea and millet were also determined. Results showed that: The general trend for soil moisture depletion increased from seedling to flowering stage and decreased at maturity stage, however, water harvesting techniques resulted in great effect on soil moisture content in three stages (seedling, flowering and maturity).All water harvesting techniques applied, increased soil moisture content at different depths (20- 40 and 60 cm) during the three growth stages V compared to rain fall treatment (control).All water harvesting techniques applied; were positively reflected in good crop establishment and improved yield components of both millet and cowpea compared to the control. Trapezoid bunds techniques (W4) significantly increased (p ≤ 0.05) total yield and final straw yield at both growing seasons compared to other water harvest techniques which showed no significant effect on all parameters (growth and yield attributes).Results also showed that the interaction of intercropping and trapezoid bunds technique relatively gave higher productivity per fadden than other techniques in both seasons. Water harvest techniques had no significant effect on crude protein and different nutritive minerals such as Ca, K, P, Ash and crude fiber for cowpea but significantly (p ≤ 0.05) increased crude protein, Mg and P percent of millet. Results showed that the interaction of intercropping and water harvest techniques significantly (p ≤ 0.05) increased crude fiber of cowpea, ash and Ca for millet.