Effect Of Some Agricultural Practices On Yield Components And Storage Ability Of Some Onion Cultivars:

A. K. I. El-kafoury

Five field experiments were carried out at the ExperimentalFarm of of the Faculty of Agriculture at Moshtohor , zagazig UniversLty Benha,Branch during the seasons of 1980 - 1981 t 1981 - 1982 and1982 - 1983 •The aim of this study was to evaluate some onion cultivarsunder the conditions of Kalubia province I the response of Giza 20 cultivarto N • P t K , Cu t Zn and Mn fertilizations as well as GA3 t NAA ,Alar and Ethere1 foliar spray. Moreover, the residual effect of suchgrowth regulators on the subsequent seed yield capacity was also takenin consideration •The first experiment was conducted to study the performance offive cultivars i.e t Behairy [local strain from Kalubia province]Giza 20 [new cultivar for Delta and Middle Egypt] t Giza 6 Mohassan[Improved Giza 6] I Shandweel 1 [New cultivar for Upper and Middle ~t]and Texas Yellow Grano 50 s [American cultivar] with respect to yieldcomponents and its quality t chemical constituents and keeping qualityof onion bulbs •The second experiment included 12 treatments i.e , 30 t 60 and90 kg N Ifed. in combination with 30 and 60 Kg P20S I fed. and ° and48 kg K20 I fed. It was conducted to study the effect of such treatmentson yield and quality as well as storageability of onion bulbs ofGiza 20 cultivar •The third experiment was conducted to study the effect of somemicronutrients i.e t copper • zinc and manganese foliar spray each attwo concentration t either as single or in combinations with eachother on the previously mentioned characteristics of onion bulbs ofGiza 20 cuItivar •The effect of foliar spray of each of GA3 ’ Alar t NAA or Etherel(each at two concentrations) on yield , quality and storageabilityof Giza 20 onion bulbs was the aim of the fourth experiment •The fifth experiment was conducted to study the residual effectof the different used growth regulators treatments of the fourth experimenton the seed yield capacity of the mother bulbsThe most important results obtained from these experiments areas follows :-1. The highest percentage of bolters was accompanied with thevariety Texas Yellow Grano t while that of doubles was in the varietiesBehairy and Shandweel l. With regard to firminess , Giza 20 and Shandweel1 Cvs , showed the highest values , followed by Behairy andGiza 6 Mohassan. Texas Yellow Grano came last in this respect • Highestbulb yield productivity was obtained by Texas Yellow Grano , followedby Giza 20 and then Behairy •2. Bulbs of Cvs Giza 20 and Behairy contained the highest percentagesof T.s.s t dry matter t N and total carbohydrates. TexasYellow Grano ranked last in this regard •3. It is advisable to alitivat Giza 20 cultivar under similarconditions of Kalubia to overcome the problem of lacking onion on markets, thus bulbs of Giza 20 cv proved to be of the best keeping qualityfollowed by Behairy t Giza 6 , Shandweel 1, meanwhile Texas YellowGrano was the worst ~ in storageability •!. Fertilization treatments had no significant effects on percentagesof either bolters or doubles of Giza ZO cultivar •5. Application of 60 + 30 + 48 kg /Eed • of N + PZOS + KzOtrespectively may be recommended to produce highest bulb yield with thebest physical and chemical characters as well as highest storageability.~. It is not advisable to spray onion plant of Giza 20 cultivarwith used microelements i.e ; Cu t Zn and Mn t Thus it did not increaseeither bulb yield or improve bulb quality or storageability •1. Repeating foliar spray of onion plants of Giza 20 cultivarfor four times with either GA3 t Alar t NAA or Etherel decreased percentagesof bolters , increased Nand P percentages and improved marketableand total yield than control. 100 - 200 ppm NAN or SO - 100 ppmEtherel proved to be the best treatments in this respect. However itincreased percentage of doubles and had no effect on T.s.s • dry weight,K and total carbohydrates percentages •8. It is advisable to spray onion plants during growth seasonwith 50 _ 100 ppm Etherel as a mean of decreasing the weight loss duringstorage , which may lead to improving storageability of stored bulbs.9. With regard to the residual effect of growth regulators usedon the produced mother bulbs, it has been found to improve the scapsformation and consequently increased seed yield productivity. Using ei~GA,Alar, NAA or Ethere! at concentrations of 100 • 500 ,200 or100 t respectively as foliar spray on onion plants proved to be amongthe best treatments in this respect •