تأثير مسافات الزراعة في المنبت و ظروف النمو بعد الغرس في نمو نبات الخس

الملخص EN

An experiment was conducted during winter season of 1992/1993 in a desert sandy soil to study the effect of thermal constant and seeding size on the vegetative growth parameters of lettuce, iMctuca sativa cv.

Omara.

Results showed that thermal constant (1000°C) gave similar head and shoot weights and leaf areas for plant grown in plastic house or tunnel or in the open field, Any increase in mean day temperature less and within thermal constant of (550-1250°C) resulted in an increase in leaf relative growth rate, mal constant (1250°C) reduced the leaf relative growth rate for large seedling.

The heaviest head fresh weight (2.6 leaves) in a plastic house with mean day temperature 18°C.