Effect of organic mulch and LEDs light colors on green bean plants (Phaseolus vulgaris L.)

Studying the positive role of applying organic mulch and different colors of LEDs light, on the growth and yield of green bean plants, were carried out during 2019/2020 and 2020/2021 seasons, at a privet farm within Suez Governorate. Seedlings of Bronco cultivar were transplanted at the 15th of October of both seasons. Two types of organic mulch i.e., chopped maize straw and chopped rice straw, addition to bare soil (control) were tested as a soil mulch treatment (factor 1). In addition, LEDs light colors i.e., red, blue and "red + blue" and without LED light were also tested (factor 2). Finally, interaction between both studied factors was also studied. Studied factors were arranged in split plot design with three replicates. Organic soil mulches were arranged in the main plots. However, LEDs light colors were arranged within the sub main plots. Vegetative growth parameters i.e., plant height, number of leaves/plant, stem diameter, number of branches/plant, fresh and dry weight of plants were measured. Moreover, percentages of nitrogen, phosphorus and potassium contents in leaves, as well as, chlorophyll reading (SPAD) were also measured. In addition, pod characteristics i.e., number of pods/plant, average pod weight and fiber content in pods, were studied as well. Finally, both early and total yield of green bean were studied. Changes in soil temperature under organic mulch treatments, as well as, bare soil were daily measured during the growing seasons. Results indicated that, in general, applying tested types of organic mulch modified soil temperature. Moreover, both tested factors were enhanced measured characters of vegetative growth, leaves content of nitrogen, phosphorus and potassium, as well as yield and its components. Furthermore, both treatments of chopped maize straw and "red + blue" LEDs light, as well as the interaction between both treatments were the most suitable for increasing productivity and quality of green bean plants.