Effect of irrigation levels, humic acid and amino acids on growth and fruiting of pomegranate trees

This investigateion wa carried out through two successive seasons of 2007 and 2008 on ýý20 years old pomegranate trees of Manfalouty cv. in a sandy soil at Ismailia Governorate ýunder drip irrigation system. This experiment was designed to: Try different water ýlevels, above and under those actually practiced in pomegranate orchards, hoping to point ýout to a rate that can give reasonable growth and yield, at the same time can save the use ýof water. Study the effect of adding humic acid and amino acids as a soil water holding ýcapacity under the low irrigation levels on growth and yield of pomegranate trees. In the ýfirst experiment the trees received the following five irrigation levels: 7 or 9 or 11 or 13 ýand 15m3/. ree/year. The highest irrigation level 15m3 induced vegetative growth, ýflowering, fruit set, fruit retention, fruit volume, fruit grain, yield and fruit cracking. ýUsing irrigation level of 13m3 recorded the highest leaf mineral (%). Also increased fruit ýjuice, TSS/ acid ratio and water use efficiency (WUE) and gave the lowest fruit cracking. ýIrrigation level 7m. decreased vegetative growth, fruit weight and yield. Also, increased ýfruit cracking, TSS, acidity, sugar, V.C and anthocyanin content. In the second ýexperiment the trees received humic acid (3248g) or amino acids (8- 16g) tree/year mixed ýwith lowest irrigation levels (7 and 9m. ) to compare with farm control (1 l m. ) . ýTreatments of 7m. integration with either humic or amino acids gave the lowest values ýof vegetative growth, flowering, fruit weight, yield, fruit grain, fruit juice and WUE and ýhighest fruit cracking, fruit chemical properties and acidity while lowest TSS/ acid ratio. ýThe opposite results were noticed with control. Treatments of 9m3 gave the moderate ývegetative growth, flowering, fruit chemical and physical properties, yield and higher ýWUE and the best treatment was 9m3 incorporation with higher doses of humic acid then ýamino acids