The Fifth Arabian Horticulture Conference, Ismailia, Egypt. March 24-28, 2001, VoL. II

RESPONSE OF LOQUAT "ERIOBOTRIA JAPONICA L." TREES TO GA3; IAA AND BAP.

BY
Bakry, KH.A. E.
Horticulture De p. Faculty of Agric., Moshtohor, Zagazig Univ. (Benha brarnch)

ABSTRACT

This study was conducted during both 1998-1999 and 1999-2000 seasons on Soucary loquat trees grown in the experimental farm at FacuIty of Agric., Moshtohor, Qalubia Governorate to improve their productivity and fruit quality by Some growth regulators application.

Thus, foliar spray with GA3; IAA and BAP at 50/100; 25/50 and 50 /100 ppm, respectively, besides water spray as control applied 3 times viz.: a)- mid Octab. (beginning of inflorescence emergence.); b)- mid Nov. (full bloom) and c)- Dec.7th (just after fruit set) were investigated The randomized complete block design with 3 replications was used  for arranging these 7 spray treatments and evaluating their influence on the following measurements: 1- cropping indication ( fruit set %; fruit retention; No. and weight of fruits ./ cluster); 2-fruit quality i.e. both physical (weight –size - pulp % -No. of seeds per fruit) and chemical properties (TSS %, acidity, total sugar and Vit.C  content).

Obtained data revealed that all cropping and. fruit quality measurements responded markedly to all GA3; IAA and BAP spray treatments compared to control GA3 surpassed statistically both IAA and BAP regardless of concentration and resulted significantly in the highest values of all yielding measurements (fruit set %, No. and weight of fruit per cluster) and most fruit physical characteristics (weight - size - pulp % per fruit) as well as nutritional value by, fruit (TSS% ,sugar and Vit. C content). In addition (GA3 at either 5O or 100 ppm significantly delayed maturation and increased No. of seeds per fruits as compared to any other treatments specially at the higher concentration which induced a complete seedless fruits. On the other hand, the response to a given/ specific treatment varied relatively from one parameter to another, whereas the response of both cropping and fruit physical measurements was more pronounced while it was less with fruit chemical properties.

INTRODUCTION

Local market in Egypt is suffering from the shortage in fruit supply through duration of early spring (late March - early May). Loquat fruit ripen during this period under" Egyptian condition and consequently it can play an important role for facing such shortage in order to meet the demand of Egyptian consumers. Moreover, the relative lake of competition from other fruit species (except the late mature varieties of some Citrus species especially sweet orange) makes attempts for spreading such fruit species (loquat) becomes more easier.

On the other hand, improving some of loquat fruit characteristics like as size, number of seeds per fruit and eating quality "sweetness & acidity" may help in making loquat fruits more acceptable by Egyptian consumer. Beside, raising its productivity could be considered as a real reason that leads to increasing cultivating area of loquat. Since, higher cropping will be reflected beneficial on return could be gained by fruit growers of loquat fruit from one hand and certainly achieved great success for providing the consumer economically with fruits at available / cheap price.

In this regard earlier investigators, demonstrated the beneficial effect of GA3 and kinetin (Galila et a!, 1991) and NAA (Ateyyeh & Qrunfteh 1997).

Therefore this work aimed to investigate foliar spray with some growth regulators i.e. GA3, BAP and IAA in order to achieve the above mentioned goals, viz improving both cropping and fruit quality of Soucary loquat trees.

MATERIALS AND METHODS

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           This study was carried out during two successive seasons of 1998-1999 and 1999-2000 on 15 years old Soucary loquat cultivar grafted on loquat rootstock grown in clay loamy soil at 5.0 x 5.0 meters a part in the experimental farm of Faculty of Agriculture Moshtohor, Qalubia Governorate. Twenty-one healthy trees were carefully selected as nearly uniform as possible in vigorous and size and received regularly the same agricultural practices adopted in the orchard.The complete randomized

The fifth Arabian Horticulture Conference, Ismailia, Egypt, March 24-28, 2001, VOL. 11

block design was used, where the experiment involved 7 treatments with 3 replicates each of one tree. The treatments were GA3 (gibbrellic acid) at 50 and 100 ppm, IAA (indol acetic acid) at 25 and 50 ppm, BAP (Benzyl arnino purine) at 50 and 100 ppm and the control treatment which was sprayed with water.

At the first sign of floral emergence, tenature shoots (bearing inflorescence) about 2 cm. in diameter were selected and labeled for  each tree . Such  shoots and born flowers on these inflorescence for every treatment 3 times with the corresponding solution. The times were: a)- just after the 1st sign of floral emergence “mid October”; b)- at full bloom, about one month later "mid November" and c)- 3 weeks later i.e. after fruit setting (end of the 1st week of December) during both experimental seasons.

The response to various seven investigated spray treatments were evaluated through determining the following fruiting measurements:

1-Fruit set %: after three weeks of full bloom (just before the 3rd spray was applied). No. of developed fruitlets were counted, then fruit set % was estimated “on the base of initial number of flowers at full bloom” according to the following equation:
                                  
                             No. of counted fruitlets
Fruit set % = ___________________________________       X 100
                          No. of  flowers at full bloom

2-Harvesting “maturation date": maturation date was determined when fruit colour was changed from green to yellow, then fruits were harvested and subjected to the following procedures:

3-Fruit retention percentage: the number of mature fruits retained till harvesting date of all labeled clusters devoted for each spray treatment were counted and estimated as percentage of total number of setting fruits.

4-Yield indication "harvested fruits per individual cluster": Picked fruits from each cluster were counted and weight then estimated either as number or weight of fruits per cluster.

5-Fruit quality: Ninety fruits were randomly sampled from each treatment (30 from each replicate/ tree) to determine the following fruit characteristics:

5-a-Fruit physical properties: Average fruit weight, size, pulp weight, pulp % and number of seeds per fruit were determined.

5-b-Fruit chemical properties: TSS%, acidity %,TSS / acid ratio, Vitamin C “mg/ 100 ml juice" and total sugars content were determined according to A.O.A.C.(1960).

Statistical analysis:

Data obtained during both seasons were statistically analysed and variances between means were compared according to Snedecor and Cochran (1967).

RESULTS AND DISCUSSION
1-Fruit set %:

           Because of the response to various spray treatments followed typically the same trend during two seasons of study, consequently an average of both seasons was graphically illustrated in Fig.(1).

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It is quite evident as shown from Figure (1) data fruit set % of Soucary loquat trees was obviously increased by any of tile investigated GA3; IAA and BAP spray treatments as compared to control. However, GA3 spray treatment at either 50 or 100 ppm exceeded markedly the other investigated ones which could be arranged into the following descending order: (a) BAP sprays at 100 and 50 ppm came second, b) IAA at 50 ppm ranked third; (c) IAA at 25 ppm and control which ranked last in this concern. Similar results were obtained by Rao  et al., (1963), Ezzat et al., (1972) and Chaudhary et at., (1992).

The Fifth Arabian Horticulture Conference, Ismailia, Egypt, March 24-28, 2001, Vol. II

استجابة أشجار البشملة للرش بحمض الجبريلليك واندول حمض الخليك والبنزايل أمينوبيورين
                                   
خالد على إبراهيم بكري
                      قسم البساتين – كلية الزراعة بمشتهر – جامعة الزقازيق ( فرع بنها )
                                               
الملخص
أجريت هذه الدراسة كمحاولة لتحسين إنتاجية وصفات جودة ثمار أشجار البشملة صنف سكري بالرش ببعض منظمات النمو ... وذلك بهدف تشجيع كل من المنتج والمستهلك من خلال توفير عائداً مجزياً للأول برفع إنتاجيتها وتلبية رغبات الثاني بتحسين جودة الثمار مما ينعكس إيجابياً على المساحة المنزرعة خاصة مع قلة المنافسة بالسوق المحلي من ثمار أنواع أخري كثيرة من الفاكهة خلال بداية فصل الربيع باستثناء بعض الأصناف المتأخرة من البرتقال.
وعليه فقد أجريت هذه التجربة خلال موسمين متتاليين هما 1998 – 1999 ، 1999 – 2000 بمزرعة كلية الزراعة بمشتهر- قليوبية لدراسة تأثير رش النورات والأفرخ الناضجة الحاملة بها بأي من حمض الجبريلليك ، أندول حمض الخليك ، بنزايل أمينوبيورين كل بتركيزين هما (50/100) ، (25/50)، (50/100) جزء من المليون على التوالي بالإضافة إلى الرش بالماء كمقارنة وذلك في ثلاثة مواعيد هي :
أ- منتصف أكتوبر (بدأ ظهور النورات)	 ب-  منتصف نوفمبر (الأزهار الكامل) جـ- نهاية الأسبوع الأول من ديسمبر (بعد العقد مباشرة). واتبع تصميم القطاعات الكاملة العشوائية في توزيع وتطبيق هذه المعاملات مع ثلاثة مكررات (شجرة / مكررة). وقد قيمت الاستجابة لهذه المعاملات من خلال القياسات الآتية المرتبطة بكل من :
أولاً : قياسات مؤشر الإنتاجية : (نسبة العقد بعد الرشة الثانية – نسبة بقاء الثمار حتي القطف ومتوسط عدد ووزن الثمار بالعنقود).
ثانيا: قياسات جودة الثمار : أ – الصفات الطبيعية (حجم ووزن الثمرة – وزن ونسبة اللب وعدد البذور بالثمرة) ، ب – الصفات الكيميائية (نسبة المواد الصلبة الذائبة الكلية ، نسبة الحموضة ، نسبة المواد الصلبة / الحموضة  ، السكريات الكلية وفيتامين ج).
ثالثاً : موعد صلاحية الثمار للقطف (النضج البستاني).
وعن أهم النتائج يمكن إيجازها في الآتي :-
أظهرت نتائج الموسمين أن جميع الصفات التي درست قد استجابت بوضوح وبصفة عامة لجميع المعاملات التي أجريت وان تفاوتت هذه الاستجابة من معاملة لأخري بحيث كانت معاملتي الرش بحمض الجبريلليك بتركيزيه هما الأكثر فعالية في هذا الصدد. وعلى جانب أخر فقد تباينت هذه الصفات نسبياً في استجابتها لكل معاملة على حدة حيث كانت قياسات مؤشر الإنتاجية (نسبة العقد -وعدد ووزن ثمار العنقود الواحد) وكذلك الصفات الطبيعية للثمار (وزن وحجم الثمرة -وزن ونسبة اللب وعدد البذور بالثمرة) الأكثر استجابة بينما أظهرت الصفات الكيميائية بصفة عامة استجابة أقل نسبياً في هذا الصدد وعموماً فإن معاملتي الرش بالجبريلليك بتركيز 50 أو100 جزء في المليون تفوقتا إحصائياً على باقي المعاملات في زيادة نسبة العقد وبقاء الثمار وحجم ووزن الثمرة وتقليل عدد البذور بالثمرة حتي أصبحت الثمار لا بذرية تماماً عند التركيز العالي كما أدي الرش بالجبريلليك إلى زيادة القيمة الغذائية للثمرة (زيادة محتواها من المواد الصلبة الذائبة – السكريات وفيتامين ج ) وإن أدت إلى تأخير نضج الثمار وصلاحيتها للقطف وهذه الصفة في حد ذاتها تعتبر ميزة أخري لإطالة فترة عرض الثمار في السوق واعطاء فرصة للمستهلك للتعرف ومن ثم الإقبال والتعود على ثمار البشملة .