Effect of phosphorous fertilization and foliar spraying with Paclobutrazol on plant growth ، productivity and quality of Peas (Pisum sativum، L.) under EL - Gabal EL – Akhdar conditions

Abstract

Tow field experiments were carried out during the two seasons of 2010/2011 and 2011/2012, at the experimental farm of the Faculty of Agricultur, Omar AL-Mokhtar University, AL-Beida, AL-Jabal EL-Akhdar region, to investigate the effects of foliar spraying of phosphore (0.0, 0.2 and 0.4%) and /or paclobutrazol (0.0, 150 and 300 ppm) on leaf chlorophyll content, vegetative growth characters, yield and its components and seed quality after harvesting on two pea cultivars (Lincolen and Alderman). The obtaind results could be summarized as follow: First: Effect of cultivars 1- Alderman cv. significantly exceeded Lincolen cv. in leaves a+b. chlorophyll content, but they did not differ in chlorophyll b. 2- The two vcs. differed in plant length and number of leaves per plant, whereas, they did not differ in fresh and dry weights of stems and leaves. 3- Alderman cv. exceeded the lincolen cv. in pod number / plant, and seed as well as pods yield per plant and per hectar, but they did not differ in pod length, width and its seed number. 4- Lincolen seed cv. exceeded the Alderman cv. in its protein content, but the opposite was true regarding p, k and carbohydrate contents.

Second: Effect of phosphorus foliar spraying. 1- Graduall increasing in phosphorus concentration gradually and significantly increased leaves chlorophyll a, b and a+b. 2-Phosphorus spraying significantly affected plant length, number and leaves area /plant in both seasons whereas, affected on remained growth Traits, only, in one season. . 3- Graduall increasing in phosphorus application till 0.4% gradually and significantly increased pod number / plant and yield of seeds and pods per plant as well as per hectar, whereas length and width of pod were not affected. 5- Spraying phosphorus had significant and positive effect on protein, carbohydrate and phosphor percentages in seeds, but had no effect on potassium content. . Third: Effect of paclobutrazol foliar spray. . 1- Foliar spraying of 150 ppm paclobutrazol was significantly the best for increasing the concentration of photosynthesis pigments 2- Foliar spraying of 150 ppm paclobutrazol led to the largest values for all plant growth traits. 3- The paclobutrazol had positive and significant effect on all yield components in both two seasons, and 150 ppm was the best.

4- The percentages of protein, carbohydrate and P in seeds were increased in both seasons and k in only first season by spraying of 150 ppm paclobutrazol.

Fourth: The combination effect between cultivars and phosphorus foliar spraying 1- Foliar spraying of 0.4% P significantly increased chlorophyll a, b and a+b in the leaves of the two used cultivars.

2- There was a positive and significant effect of spraying phosphorus for increasing of all vegetative growth traits of the two cultivars. 0.4% P was the best, but did not differ significantly with 0.2% P in some vegetative parameters . . 3- The combination of cultivars and phosphorus spraying had significant effect on pod number / plant, yield of seed and pods per plant and per hectar, but had no significant effect neither on length and width of pod nor on number of seeds / pod, in both seasons. 6- The protein, carbohydrate, and phosphorus perecentages in pea seeds were affected by the combination between cultivars and phosphorus spraying in both two seasons, and the quality of seeds was gradually increased with increasing phosphorus concentrations.

Fifth: Effect of the combination between cultivars and Paclobutrazol foliar spraying 1- Foliar spraying by 150 ppm pb was significantly the best for increasing the concentrations of photosynthesis pigments in two used cultivars . 2-Spraying Pb . generally, redused plant height, comparing to untreated control in both cultivars, whereas, increased the other vegetative growth characters. 150 ppm Pb was the best, but the benfical effect was redused by increasing Pb concentration. 3- The combination between cultivars and Pb hah a significant and positive effect on all yield components. 7- All studid seed quality component affected by the combination between cultivars and Pb, in both seasons.

Sixth: Effect of combination between foliar spraying of phosphorus and Pb. 1- The combination between 0.4% P and 150 ppm Pb was significantly the best for increasing chlorophyll a, b and a+b conten in leaves. 2- Spraying of 150 ppm Pb at all phosphorus levels had a superior effect for increasing all vegetative growth traits, in both two seasons. 3- The combination of foliar spraying of phosphorus and Pb had a significant effect in all yield components, i. e. length and width of pod, seed number / pod, yield / plant and hectar, in both seasons. 4- Protien, carbohydrate, P and k % in seed were significantly affected by the combination between phosphorus and Pb, in both seasons.

Seventh: Effect of triple combination among cultivars, and foliar spraying of phosphorus and Pb. 1- The combination between 0.4% P and 150 ppm Pb was the best for increasing chl. a, b and a+b but did not differ significantly when P concentration was zero or 0.2 % in both cultivars. 2- There was significant effect for the triple combination on all plant growth traits in both seasons, with the exception of leaves fresh weight in the first seasons and stem fresh weight in second one. 3- The combination between the three studied factors had a significant effect on all yield and its components, and the 0.4%P + 150 ppm Pb was the best for increasing their values for both cultivars. 4- The combination between 0.4% P and 150 ppm Pb exceeded the other combination, in Alderman cv., in increasing protein, carbohydrate, P and k contents in pea seeds, in both seasons. Moreover, the same mentioned combination increased the quality of pea seeds cv. lincolen with no significant differences between it and some other combinations. Conclusion and Recommendations. From the results of this study it should be concluded that, the best combination treatment of the three studied factors that attained the highest growth, yield and quality of the two tested cultivars was foliar spraying with 0.4% P +150 ppm Pb for each cultivar. So, according to the results of this study, we recommend to cultivate Alderman cultivar but not lincolen cv, because the first cv. yielded 4448 kg seed / ha and 7503 kg pods / ha, as average of the two seasons, and that exceeded the licolen cv. by 258 and 277 %, respectively . Moreover, Alderman cv. seeds had higher seed quality, i.e ., more protein, carbohydrate, P and K % than lincolen cv.