This work was conducted during 2000 & 2001 seasons on fruitful trees of 5 pecan cvs. (Curtis; Mahan; Money Maker; Stuart and Van Deman grown in Toukh and Al-Khanka regions, Qalubia Gevernorate. It was hoped to determine the suitable fertilizer/s for Curtis (an important commercially cultivated cv.) through studying their flowering characteristics (Expe.,I) and both productivity and fruit quality of Curtis cv. in response to cross pollination with pollens of four investigated pollinizers (Exp.,II).
Obtained results revealed that date/duration of all investigated flowering characteristics varied greatly not only from one cultivar to another but also even with the same cultivar. Hence, flowering dates of both pistillate and staminate flowers for each individual cv., as well as maturation date of its sex organs (stigma receptivity and pollen shedding) didn’t fully coincided in either both start and dates of blooming or duration extended along the whole and full bloom stages of both flower types. Meanwhile, all 5 cultivars tended strongly to be dichogmous, but according to earliness or lateness in blooming and maturation date of one flower type (sex organ) than the other, two opposite patterns were detected. Curtis; Mahan; Money Maker and Stuart cvs. were protogynous (blooming of their pistillate flowers and stigmata receptivity took place earlier than pollen shedding of their Staminates.), While with van Deman the pattern took the other way around and classified as a protandrous.
As for the influence of pollination treatments on productivity indicators of Curtis cv. expressed as fruit set% ; mature fruits picked per either an individual pistillate inflorescence or tree (4 tigged limbs per each), as well as its fruit quality physical and chemical properties, i.e., (average fruit wt., dimensions and shape index) and (kernel oil, proteins; carbohydrates and sugars), respectively. Data obtained during both seasons proved that all cross pollination treatments were statistically more effective than the naturally self (open) pollinated Curtis trees, however cross pollination with van Deman pollens was the superior and surpassed significantly the other cross pollination treatments. Such trend was true especially as fruit set%; three other measurements of productivity and average fruit weight and length of Curtis fruits, beside their kernel oil and protein contents.
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