تأثير الارتفاع و عدد و مواعيد القرط في بعض صفات النمو و إنتاج الكتلة الحية لشتلات اللوسينيا Leucaena leucocephala

الملخص EN

The present study was conducted in Ninevah forest to study the effects of the height, numbers and date of pollarding of the shoots of leucaena at one years age.

The pollarding was done monthly at fired different heights above ground level namely, 15, 30 and 45 cm to stimulate the regrowth of the plant and, arimize biomass production.

The results indicated the following Growth characteristics : -The highest average monthly grouth in length (4.13 cm) obtained the pollarding was done at 15 cm height, while the highest average in diameter (0.89 mm) occurred in plants pollared at 30 cm above the ground level.

With respect to the number of pollarding, it appeared, that pollarding for one time was the best in comparing with the other number of pollarding since it gave the highest average of minthly growth in length (13.88 cm) and diameter (1.22 mm) As for pollarding dates, october the first was the best achieving.

The highest increase in the average monthly grow the in hieght (41.94 cm) and in diameter (2.83 cm) among the other pollarding dates.

Biomass production was the best height of pollarding which gave the best increase in dry weight of the shoots per pollard and the accumalated mass due to the total pollards was 45 cm above the ground level a since it gave the highest averages and 154.64 gm), on the other hand, pollarding for one time was better than the other pollarding numbers in giving.

The highest values in dry weight and in the accumlated total due to pollards in regard to the date of pollarding, first of November was the best ingiving the highest mean (197.82 g) in dry weight of shoots.