الفهرس 
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Abstract
Field experiments were carried out at the Agricultural Research and Ex.?eriment Station, Facult,r of Agriculture at Moshtohor. Zagallig University in the two sUcGessive growing
seasons of 1981 and 1982. Soil analysis of the experunental plots indicated a
clay soil texture, pH value of 7.9 and 2.54% organis matter content. Two st~dies were performed.
-Growth and Yield of ~mize as Affected by M~thods of Planting
and Thinning Date13 : ’llhisexperiment aimed to stUdy the effect of three
planting methods and four thinning dates on the growth
behaviour, quantitative and qualitative characters of maize plants”
The cornnercial distributed n:.aize cultivar Pioneer 514 (a dOUble hybrJ.d) was used in this study. Nitrogen
was applied at a rate of 90 kg/fd. Normal cultural practices
were applied properly. The experiment included 12 treatments which were
the combination of three planting methods and four thinning
dates.A - Planting rrethods were: Wet planting (Herati), dry planting (Afir) and flat planting (lliinimum tillage).
In all OJ~ the three planting me thods maize was grown on ridged rows of 70 em apart at 30 em distance between
hills where 4 kernels were planted per hill. B - Thinning dates
were at 15, 20, 25 and 30 days
from planting. This expe”iment in particular was designed as a ”;>litplot
With six rE~licates. Methods of planting were the main plots and thinning dates were randomly distributed in the SUb-plots. The SUb-plot area was 21 m2•
The main r’?sults could be summarized as follows : Effect of plantll~ methods:
1. The e££Ect o£ planting methods on root dry weight of maize plants was significant in the two studied seasons.
Wet plantiLg method produced the highest dry weight of roots, followed b;,dry planting, then the flat planting
where the lowest (~y weight of roots was produced. Maize pLan t s grown under wet planting method reached tasselir..gand silking earlier than those of dry and flat method~. However, the differe~ces were not significant.
J. Plant beight of maize plants was not significantly affected by planting methods. However, plants grown under
flat method were somewhat shorter than for the wet and dry planting methods.
4. The eff2ct of planting methods on the ear height was significant ~nly in the first season, having the same
trend in the second season. Highest ear height was obtained by using wet planting method, 5. Maize plants grown under wet method Vlere significantly
superior :_n stem diame ter than those grown under flat method.6. Axea of the topmost ear leaf was not significantly
affected by the various planting methods 7. Wet and dry planting methods increased ear length significantly as compared with flat method in the first
growing season, where the wet method produced the highest ear length. However, the difference was not significant in the second season.
8. P’LantLng method did not exhibit any significant effect on the ear diameter as well as nwnber of rows/ear
in both of the c c.I tivated seasons.
9. Wet plan.ting method produced the highest number of kernels per ear followed by the dry and then flat planting method in the two seasons.
10. Wet planting method induced a slight increase in ear weight over dry and flat planting methods, but these
increases were not significant in both seasons. 11. Planting method did not exhibit any significant effect on the number of ears per plant in both seasons 12. There was no significant difference in the number
of plants per plot at harvest as a result of using the various planting methods. However ~ wet planting method
had the highest n~ber of plants per plot as compared to dry and flat planting methods. 13. Plants g::-ownunder wet and d.ryplant ing methods
exceeded the flat method in grain yield per plant in the two cultivated seasons. However, such increase was significant only in the second season.
14. Shelling percentage as well as IOO-kernel weight, were not significantly affected by the various planting
methods.15. Methods of planting did not significantly affect the grain yield. Grain yield in wet planting method
exceeded that in the dry and flat methods by 7.1 and 10.6% in 1981 and by 3.8 and 8.3% in 1982 season, but differences failed to reach tte level of significance.II. Effect of various thinning dates : 1. Thinning date had a significant effect on the dry weight of roots. Early thinning produced the highest dry root weight per plant, while the late thinning produced
the lowest dry weight. 2. Tasselin,s and silking wer-e significantly affected
by the different thinning dates in both seasons. Earlier tasseling and siLcing were obtained at the earlier thinning
date (15 days from planting).
3. Early th.Lnning increased plant height and ear position on the plant in both seasons. However, the increase
in the ear posi t i.on was not significant in the second season.
Thinning at 15 and 30 days from planting produced the tallest
and the shortest maizeplant.1respectively.
4. Early th:_nning (15 days from planting) significantly increased the stem diameter and leaf area as compared
to late thinning (30 days from planting).5. The ear length and ear diameter increased significantly
due to tae early thinning as compared to the late thinning date.
6. The effect of various thinning dates on the number of rows per ear w~s not significant having no specific trend.
7. There were significant differences in the nwmberof kernels per ear between the early and the late thinning dates.
8. Early thinning (15 days from planting) gave a significant incre~se in ear weight in the first and second
seasons as compared with late thinning (30 days from planting).
9. Time of thinning had a significant effect on the grain yield per plant in the two cultivated seasons. The
delay in thinning date (30 days from planting) caused a decrease in grain weight per plant by about 20.6% and
28.2% in 1981 and 1982 seasons, respectively as compared with the early thinning.10. Shelling percentage was significantly affected by thinning dates only in the second growing season. The highest shelling )ercentage was produced by thinning at 15 days from planting in both seasons.
11. There was no appreciable effect obtained by different thinning dates on the number of plants per plot at
harvesting. whereas the highest number of plant per plot at harvesting waS obtained by thinning either after 20 or
30 days from planting. 12. The ea~ly thinning gave the highest number of ears
per plant, while t.ae late thinning dete gave the lowset number. 13. Thinning dates had a significant effect on 100 kernel weight in the two growing seasons. The early thinning (15 days from planting) produced higher laO-kernel weight, then the lOO-kernel was decreased toward delayingthinning.
14. Thinning dates had a significant effect on the grain yield per j’eddan in both of the studied seasons. EarlY thinning (:L5 days from planting) outyielded all of the other later t.hinning dates (20, 25 and 30 days from
planting) by 50, 326 and 580 kg/fed. in 1981 season, respectively, corresponding to 192, 466,and 748 kg/fed. in 1982 season. III. Interaction effl-;!ctS: The effect of the interaction between varioUS planting
methods and thinning dates for tDe studied growth characters and yield as well as yield components were not
significant in the two growing seasons.