Response of Cotton Plant to Spraying Some Natural Materials Under Water Stress Conditions
Journal of Plant Production
ABSTEACT Two field experiments were carried out at El-Gemmeiza Agricultural Research Station, El-Gharbia Governorate during the two successive seasons of 2015 and 2016. These experiments were conducted to find out the proper irrigation interval and the effect of natural material which reduce the negative effect of water stress as well as their interaction on leaf chemical composition, growth, flowering habit, earliness parameters, seed cotton yield and its components and fiber quality of the
... r quality of the Egyptian cotton cultivar Giza 86. A split plot design with three replicates was used in both seasons, where the main plots were assigned to three irrigation intervals (15, 30 and 45 days) and the sub-plots contained natural materials (without, glycine betaine (600 ppm), potassium citrate (3g/l) and salsalic acid (200 ppm) The important results could be summarized as follows: Irrigating intervals gave significant effect on l e a f total chlorophyll, carotenoids, phenols and proline content at 114 days, when irrigated every 45 d a ys followed by irrigated every 30 and 15 day in a descending order. Irrigation every 15 days significantly increased plant height at harvest, number of fruiting branches/plant, number of flowers/plant, boll weight and decreased setting and earliness percentages in both seasons as compared with the other two irrigation intervals (every 30 and 45 days). However, the higher number of open bolls/plant and seed cotton yield / fed were obtained from plants which irrigated every 30 days. Irrigation intervals had insignificant effect on seed index and significant effect on lint % in both seasons. The highest value of lint % was resulted from irrigated plants every 45 days. Spraying with natural materials significantly affected leaf total chlorophyll, phenols and proline content, in favor of spraying potassium citrate and significantly affected leaf carotenoids content at, in favor of spraying salsalic acidSpraying with natural materials significantly affected boll weight and number of open bolls/plant in both seasons in favor of spraying glycine betaine and potassium citrate. Application of salsalic acid or glycine betaine gave significant increase in lint % and insignificant effect on seed index in both seasons. Spraying cotton plants with glycine betaine lead to a significant increase in seed cotton yield per fed. Untreated Plants caused a significant increase in plant height at harvest and number of fruiting branches/plant in both seasons as compared with the plants which received glycine betaine, potassium citrate and salsalic acid. Concerning the interaction between irrigation intervals and natural materials, there is a significant interaction effect with regard to l e a f total chlorophyll, carotenoids, phenols and proline contents, in favor of irrigated cotton plants every 45 days and spraying with potassium citrate for l e a f total chlorophyll, phenols and proline contents and in favor of irrigated cotton plants every 45 days and spraying with salsalic acid for l e a f carotenoids content. Irrigation every 30 days and spraying with potassium citrate produced the highest values of lint % in both seasons. The interaction gave insignificant effect on seed index, Presley index and micronaire reading in both seasons. The combined treatment of irrigation interval every 30 days when combined with glycine betaine at the concentration (600 ppm) gave significant increase in seed cotton yield / fed (kentar) in both seasons. The flowering curve in irrigation every 30 and 45 days was higher, start earlier and ending earlier as compared to the flowering curves in the irrigation every 15 days. It could be concluding that irrigation cotton plants every 30 days in combination with spraying with glycine betaine (600 ppm) or potassium citrate (3g/l) three times (at the squaring stage, flowering stage and at the top of flowering) under El-Gemmeiza condition). Also, it could be concluding that irrigation every 45 days in combination with glycine betaine (600 ppm) at the end of water sources and water shortage.