Improving Yield and Fruit Quality of Washington Navel Orange Using Foliar Applications of Some Natural Biostimulants.

Abstract

Field experiment was carried out during two successive seasons of 2012 and 2013 on Washington Navel sweet orange cultivar (Citrus sinemsis, L) onto sour orange rootstock (C. aurantium , L) grown in well drainage clay loam soil of a commercial orchard located in Shiwah Valley (30°51'55.78"N, 31°16'23.14"E), near Aga city, Dakahleia Governorate, Egypt. The investigation was designed to throw some light on the effect of two natural biostimulants, i.e., Milagrow at 10, 15 and 20 ppm (extracted from pollen grains of rape seed (Brassica napus) as a source of brassinolide phytohormone) and yeast extract at 1000, 1500 and 2000 ppm on fruit set, fruit drop, yield and fruit quality of Washington Navel orange trees. The natural biostimulants were tested as foliar sprays at full bloom stage and one month later. Data indicated that, all biostimulants treatments increased fruit set, yield and fruit quality and decreased fruit drop as compared with control treatment. Data also revealed that, foliar sprays of trees by Milagrow at 15 and 20 ppm were superior for inducing the highest increase of fruit set and yield, in addition yeast extract at 2000 ppm comparing with rest concentrations of both tested biostimulants. On the other hand, no significant differences were observed among all tested concentrations of two natural biostimulants with respect to fruit weight in two seasons. The foliar applications of Milagrow and/or yeast extract increased fruit SSC and reduced acidity contents in fruit juice as compared with control treatment. Moreover, it was noticed that trees sprayed with two tested biostimulants gave the best results for reducing fruit drop. It could be recommended that best treatment for increasing yield and improving fruit quality was spraying Washington Navel sweet orange cultivar with Milagrow at 20 ppm and yeast extract at 2000 ppm during full bloom stage and one month later especially in the same conditions to experimental area.

Effects of Silicon and Yeast Extract on Growth, Flowering and Yield of Banana (Musa cavendishii L.)

“…Plants treated with silicon at 3% and sprayed with yeast at 20g/l level, bloom earlier by about 20 days compared to the control. These results are in agreement with those obtained by Abd-El- Hamied (2015), Ahmed et al, 2013 andRoshdy (2014) and El-Boray et al, (2015) on other plant species.…”

“…The high own content of yeast extract from nutrients as well as amino acids, vitamins and phytohormones surely reflected on enhancing the biosyntheses of pigments and total carbohydrates consequently advancing fruit quality (Soliman et al 2000). These results are in agreement with those reported by El-Shazly and Mustafa (2013) and El-Boray et al (2015) with Neval orange who reported that active dry yeast caused a significant increases in T.S. and vitamin C content of fruits.…”

“…Improving growth and productivity of different plant species by application of either Si or yeast extract were recorded with different investigators. El-Boray et al, (2015) on orange reported that the positive effects and benefits of applying yeast extract as a natural biofertilizers were attributed to its own different nutrients, greater amounts of vitamins and cytokinins as natural plant hormones. They added that it is very effective as shown with orange in releasing carbon dioxide as well as stimulating photosynthesis, yield and fruit quality physically and chemically.…”

Effect of some Biological Stimulants and Kaolin Particles Sprays on Fruit Retention, Productivity and Fruit Quality of Washington Navel Orange Trees

“…Orange occupies the first rank among all fruits cultivated in Egypt, with about more than four million metric tons produced in 2015 (El-Boray et al, 2015), and Egypt exports of orange exceeded 1.6 million tons in /2017(USDA 2016, 2017. Navel orange is the most important citrus fruit in Egypt.…”

Use of Natural Raw Material Mixture and Natural Raw Potassium as Substitute for Chemical Fertilizers in Feeding Washington Navel Orange Trees under Kafr El Sheikh Conditions.

“…Also natural raw material mixture and natural raw potassium (feldspar) are a good alternative to reduce uses of chemical fertilizers (Abdel Rahman et al, 2009 andEman et al, 2010). In this respect, several studies were accomplished for producing organic fruits through avoiding partially the application of chemicals fertilizers and encouraging the application of organic and natural raw material (rocks) fertilizers ( El-Boray et al,2007, Abdel-Hak et al, 2012, Shaheen et al, 2013, El-Iraqy 2014, El-Boray et al .,2015and Mostafa and Abdel Rahman 2015.…”