Response of Some Soybean Cultivars to Low Light Intensity under Different Intercropping Patterns with Maize

Abstract

A two-year study was carried out at Mallawi Agricultural Experiments and Research Station, A.R.C., El-Minia governorate, Egypt, during 2014 and 2015 seasons to determine the compatible soybean cultivar with high maize plant density to achieve farmer's benefit under intercropping conditions. Alternating ridges (70 cm width) between maize and soybean were used as 1:3, 2:4, 2:2, 3:3 and 4:2, respectively, in addition to sole culture of both crops. Local maize cultivar T.W.C. 310 was grown in one plant per hill distanced at 30 cm under intercropping and sole cultures, meanwhile local soybean cultivars (Giza 22, Giza 82 and Giza 111) were drilled in both sides of the ridge (two plants/hill distanced at 15 cm) under intercropping and sole cultures. A split plot distribution in randomized complete block design with three replications was used. The results indicated that maize yield attributes were increased significantly by decreasing maize plant density from 67 to 25% of sole maize under intercropping conditions, meanwhile the converse was true for plant height and grain yield per ha. All the studied maize traits were not affected by soybean cultivars. Also, all the studied maize traits were not affected the interaction between intercropping patterns and soybean cultivars. Soybean yield and its attributes were increased significantly by decreasing maize plant density from 67 to 25% of sole maize under intercropping conditions except plant height. The late-maturing soybean cultivar Giza 22 recorded the highest values of intercepted light intensity within soybean canopy, number of pods per plant, seed index, seed yields per plant and per ha, meanwhile, the highest values of biological yield per ha, plant height and number of branches per plant were recorded for soybean cultivar Giza 111. Soybean cultivar Giza 22 gave the highest seed yield per plant compared to the other cultivars under all the intercropping patterns. Relative yield of soybean showed that the earlymaturing soybean cultivar Giza 82 is better adapted to low light intensity than the other cultivars. Land equivalent ratio and area time equivalent ratio values for intercrops were greater than 1.00 indicating less land requirements of intercropping patterns than sole maize. Growing four maize ridges alternating with two ridges of soybean cultivar Giza 82 achieved the highest net return compared to sole maize.

Interplanting Some Soybean Cultivars with Mandarin Trees in Sandy Soil

“…It is known that shading during early flowering stage decreased assimilates availability to the developing reproductive structures, and thereby pod number at harvest [41]. These results are in accordance with those obtained by Abdel-Wahab and Abd El-Rahman [42] who showed that intercropping decreased the number of pods per plant. [43], Egbe [44] and Metwally et al [45] who investigated that intercropped soybean produced lower seed yield than their sole crop counterparts.…”

“…It is likely that canopies architectures of soybean cultivars Giza 111 and Giza 22 were more compatible with adverse effects of mandarin shading, which reflected positively on their productivity per unit area. With regard to soybean cultivars Giza 82, it had self regulation mechanism of redistributing the available assimilates to components, in an attempt to maintain or improve yield under high shading intensity [42]. These data show that each of these two factors acts dependently on all the studied traits of soybean.…”

Intercropping Some Soybean Genotypes with Corn for Producing Soybean Seeds, Quality and Land Equivalent Ratios

“…In the meantime, intercropping had no discernible impact on the seed index of the soybean genotypes C14, Giza 22, Giza 35 and PI 399035. The narrow leaves of the soybean cultivar Giza 22 enhanced the number of reproductive sinks under intercropping and the availability of light 34,42 . The soybean cultivar Giza 35, on the other hand, was able to withstand all of the tested insect attacks under intercropping 37 because of its canopy structure, which allowed more sun radiation to reach the plant's other leaves 43 .…”

Physiological Characteristics of Soybean Leaves with and without Shading at Palm Oil Plantation, West Papua

“…Data shows that soybean harvested area in West Papua in the period 2009 -2011 was 1150, 571 and 375 ha with an average productivity of 1.05 tons/ha. The main limiting factor for planting in the shade is the low intensity of sunlight (Mathew et al 2000;Bellaloui et al 2012;Abdel-Wahab). According to Asadi et al (1997) oil palm plantations of 2-3 years TBM cause shading of 33-50%, while 20% shade is classified as inappropriate for soybeans (Adisarwanto et al 2000).…”