الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 120 |  |  |
| | | from | 120 | | |
Abstract
Two field experiments were conducted at Mallawi Agricultural Research Station, Minia Governorate, ARC, during two summer seasons of 2018 and 2019. The present work aimed to study the effect of intercropping of oil summer crops on maize under different combinations of Nano and mineral nitrogen fertilizer.
Maize (Zea maize, l) cv. Giza 168 (yellow corn) was the main crop , soybean (Glycine max L.) Giza111, groundnut (Arachis hypogeae L.) Giza 6 and sesame(Sesamum indicum L.), Shindauel 3 were the sub crops
The experimental design was Randomized Complete Blocks Design in split – plot arrangement with three replicates. The main plots were assigned to the three companion-crops. The sub-plots included nitrogen fertilization treatments from each crop. The sub – plot area was 28 m2 consisting of 5 beds, each of bed was 140 cm in width and 4m in length for intercropping treatments.
The recorded data:
i. Maize characters:
Plant height (cm), ear height (cm), stem diameter (cm), number of ears /plant, ear length (cm), ear diameter (cm), number of grains/ear, weight of grain/ear (g), weight of ear (g), weight of 100 grain (g)and grain yield /fed (ardab).
ii. Companion crops characters:
a- Soybean characters:
Plant height (cm), number of branches/plant, number of pods/plant, 100seed weight (g), seed yield/fed (kg), and straw yield (ton/fed).
b- Groundnut characters:
Plant height(cm), number of branches/plant, number of pods/plant, 100-seed weight(g), Biological yield/plant(g), green yield (ton/fed) and pods yield fed(ardab),
c- Sesame characters:
Plant height (cm), height of first capsule (cm), number of capsules/plant, 1000 seed weight(g), seed yield /plant(g) and seed yield/fed(ardab).
iii. Competitive relationship and yield advantage : Land equivalent ratio (LER), Land equivalent coefficient (LEC), competitive ratio (CR), and Aggressivity (Agg)
iv. Total returns and monetary advantage index (MAI)
The results could be summarized as follows:
i. Maize:
1- Effect of the companion crop species:
The results indicated that intercropping maize with soybean and groundnuts were less competitive compared to sesame with maize, groundnut was less competitive than soybean in both seasons. Intercropping groundnut with maize gave the highest values of grain yield (23.25 & 21.61 ardab/fad ), whereas sesame intercropping with maize gave the lowest values of grain yield (20.69 &17.40 ardab/fad) in the first and second seasons, respectively.
2- Effect of different combinations of nitrogen fertilizer:
The data of combination fertilizer percentages revealed that the highest values for maize traits resulted from application of 75% nano N +25% mineral N fertilization, while the lowest values were recorded for 100% mineral N fertilizer in both seasons.
The application of 75% nano N+ 25% mineral N fertilization to maize gave the highest values of grain yield of 26.33 and 25.24 ardab/fad in the first and second seasons, respectively, owing to increase of yield component traits. Oppositely, the application of 100 % mineral N fertilization of maize gave the lowest values of grain yield of 16.19 and 13.73 ardab/fad in the first and second seasons, respectively.
ii. Companion crops:
a- Soybean:
The results showed that all studied traits were reduced with intercropping soybean with maize in both seasons. Pure stand produced seed yield/fed three folds of intercropped soybean in both seasons .The data showed significant differences in all studied characters of soybean, for different fertilizer percentages, except plant height and number of branches/plant. Application 50% Nano N fertilizer+50% mineral N fertilizer significantly increased seed yield of soybean compared to of utilization of other combinations of N fertilizer .
b- Groundnut
The results indicated that intercropping groundnut with maize decreased all studied traits of groundnut compared to pure stand in both seasons. Pure stand gave 2 folds pods yield/fed of intercropped groundnut.
Different combinations of N fertilizer showed significant effect on all characters of groundnut in both seasons. Fertilization by 50% nano N +50 mineral N produced the highest values of studied traits. Oppositely, the lowest values were achieved with fertilization by 100% mineral N.
c- Sesame
All studied traits of sesame were reduced due to intercropped sesame with maize in both seasons. Pure stand of sesame produced seed yield/fed equal about 2 folds of intercropped sesame.
The results recorded significant effect for all characters of sesame with different N fertilizer percentages in both seasons, except first capsule height. The highest seed yield/fed of 2.70 and 3.39 ardab/fed were detected by application of 50%Nano N + 50% mineral N in first and second seasons, respectively.
Competitive relationships:
Land equivalent ratio (LER):
Data clearly indicated that land equivalent ratio in all treatments of the interaction between maize and nano-mineral N fertilization were greater than one in both seasons, indicating that it is advantageous to grow maize and soybean, groundnut and sesame compared to in solid culture. Intercropping groundnut with maize and using 75% nano N fertilizer +25% mineral N fertilizer recorded the highest values for LER. Intercropping soybean with maize with using 100 % mineral N fertilizer recorded the lowest values for (LER).
-Land equivalent coefficient (LEC)
The results revealed that intercropping oil crops on maize and their interaction on the LEC of intercropping maize exceeded 0.25 in the intercrop combinations used. Intercropping 50% groundnut with100% maize plus75% nano N and 25% mineral N fertilizer recorded the highest values for LEC in both season. LEC values followed a trend similar to that of LER.
- Effect of various cropping systems on competitive ratio (CR):
Data revealed that the lowest values of CR were recorded for intercropping sesame with maize in the 1 st and 2 nd seasons. However, the highest values of CR were recorded for intercropping soybean with maize in the 1 st and 2 nd seasons.
- Effect of various cropping systems on Aggressivity(Agg)
The results showed that aggressivity values of maize were positive, whereas values of soybean were negative in both seasons, meaning that maize was dominant and soybean was dominated.
-Total returns and monetary advantage index (MAI):
Data of economic analysis revealed that the net return of using 75% nano N plus25 % mineral N fertilizer for maize and groundnut intercrop recorded 13875 and 11922 L.E. fed-1 in first and second seasons, respectively. While The monetary advantage index (MAI) recorded were 13.303 and 11.350 L.E. fed-1, meanwhile, the lowest net return was recorded for intercropping soybean with maize received rate of 100% mineral N fertilizer of 1022 and 968 L.E. fed-1 and monetary advantage index (MAI) of 0.128 and 0.181 L.E. fed-1 in the first and second seasons, respectively.