Spiderplant (Cleome gynandra) is an African indigenous vegetable (AIV) in many parts of sub-Saharan Africa, especially in most countries in eastern and southern Africa, where it is a semi-cultivated popular tropical species. In Kenya, it is among the most popular AIVs, particularly in the western and coastal regions. Seed supply systems for spiderplant is largely local and whatever material that is available is often of poor quality, mainly due to lack of development of seed quality testing protocols, thus hampering the correct assessment of the quality of seed used for sowing. The study aimed at determining temperature and light optima for seed germination and seedling development of spiderplant morphotypes from western Kenya. The original spiderplant seeds for the study were sourced from farmers in Kakamega District and from wildly growing plants within Chepkoilel Campus in Uasin Gishu District, both in western Kenya. Four morphotypes were identified and selected based on the presence or absence of anthocyanins on their stems and petioles, respectively. Tests on seed quality aspects were done at the Bioscience Business Unit at Plant Research International, Wageningen, The Netherlands. Determination of optimum temperature for seed germination was conducted by incubating three replicates of 100 seeds each of the four morphotypes at constant temperatures of 20, 25, 30, 35, 40 and 45OC, respectively. In order to determine the light regime for seed germination and optimum temperature for seedling development four replicates of 50 seeds each were incubated at constant temperatures of 30 and 35 OC at 8-hr light day-1 and 0-hr light day-1 (in 24-hr darkness), respectively. Data analysis (ANOVA, statistical descriptors and t-tests) were done using statistical package SeedCalculator 3.0. Germination was strongly influenced by temperature showing declines at both extremes of 20 and 45OC and optimum of 35 and 40OC. Light had no influence on germination since seeds germinated equally well under light and in the dark. Seedling development was strongly influenced by temperature with higher percentage of normal seedlings at 30OC than at 35OC. It is concluded that while temperature had an effect on seed germination performance and seedling development, light on the other hand showed no effect on seed germination for the spiderplant morphotypes studied. However, white light is required in order to aid in seedling evaluation.
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