This investigation was carried out during 2002 and 2003 seasons on 15·
year-old Thompson seedless grape variety "Banaty" grown at Ebshan, Kafr EI-
Sheikh. where the soil is moderately alkaline to study the effecl of soil mulching with
three different materials (black polyethylene, rice straw and bean straw) comparing
with bare soil as a control. The obtained results could be summarized as follows: Black polyethylene (BPE) mulching treatment was the most effective on keeping
soil lemperature more higher by about 2-3°C than of bare soil and other organic
mulching treatments which reduced soil temperature at 7 a.m. and 1 p.rn. due to
shedding effect of rice and bean straw. In addition, all mulching materials
increased soil moisture content and the effect was more pronounced by BPE
Ireatmenl due to reducing evaporation ofwaterfrom SOil surface. All mulching materials caused significant increased in shoot length (cm) during
the growing seasons as well as number and fresh weight of fibrous roo Is (g) at 0-
30 and 30-60 cm soil depth, BPE treatment produced the highest values and rice
straw came the second. then followed by bean straw material in both seasons. The positive effect of soil mulching extended to increase Ihe uptake of N. P, K, Ca
and Mg nutrients as well as some organic substances in leaves such as
chlorophyll and total carbohydrates, especially by rice straw treatment. Soil mulching with rice straw, followed by bean straw not only produced the
highest fruit set percentage and yield as number and weight of clusters per vine,
but also caused a significant improvement in most physical properties of cluster
without any adverse effects on juice chemical properties. Rice straw as soil mulching material attained the highest adhesion force of berries
from its pedicels (PAF) on the cluster when compared with the control and other
mulching materials in the two seasons. Also, this treatment recorded the highest
force needed to crush berry (BCF) as g/cm²at harvest time due to increasing
flesh firmness of berries.