The objective of this experiment was to measure the effect of water stress on nitrogen fixation in four cowpea varieties. Plants were grown in a greenhouse and watered with 5, 10, and 15 ml of the...

The objective of this experiment was to measure the effect of water stress on nitrogen fixation in four cowpea varieties. Plants were grown in a greenhouse and watered with 5, 10, and 15 ml of the appropriate nutrient solution. Fifty-five days after planting, the nitrogen nodules were removed from the plants and counted and weighed. The entire experiment was replicated three times. The response variable to be analyzed is the weight of the nitrogen nodule. The data are given in Table 10.26. Perform the appropriate analysis to determine the effect of water stress.