Effect of Growth Habit of Beans on Tolerance to Competition from Maize When Intercropped¹

Abstract

Three trials were planted at CIAT, Colombia, with selected lines of red seeded beans (Phaseolus vulgaris L.), representing the best that has emerged from breeding of each growth habit, in order to study the relationship between growth habit and competitive ability with maize (Zea mays L.) when intercropped. Treatments included sole cropping without stakes, and with stakes that varied in height from 1 m to 2 m, and intercropping with short and tall maize cultivars. Highly significant interactions of bean lines by cropping systems were found. Correlations between yields of bean lines in sole cropping without stakes and intercropped were negative or zero, whereas correlations between sole cropping with stakes and intercropping were significant and positive. Internode length increased with growth habit, from bush to climbing types, and indeterminate types were stimulated to develop more main stem nodes either by the presence of a stake or a maize plant. Climbing types (Type IV) tended be later to flowering and maturity and were more competitive with the maize than bush types. Harvest index was reduced less in the Type IV lines when intercropped with maize than in the bush lines (Types I, II, and III). In a breeding program, selection in crosses among growth habits will tend towards bush types of beans when selected in sole cropping, and climbing types in intercropping.

Development of crop cultivars by honeycomb breeding

“…This is supported by the finding that in intercropping studies which involve different cultivars of the same crop, a significant genotype by cropping system interaction occurs, demonstrating that intercropping systems favour more genotypes that perform poorly as sole crops rather than the highly performing when grown alone (Davis et al 1984;Tsay et al 1988;Santalla et al 2001;Tefera and Tana 2002;Hauggaard-Nielsen and Jenssen 2001;Atuahene-Amankwa et al 2004;O'Leary and Smith 2004;Gebeyehu et al 2006).…”

“…The major reason is the unequal share of resources in the presence of competition, that the growth and the development of individuals are suppressed unevenly Fasoula 1997a, 2002;Fasoula and Tollenaar 2005). A particular cause also is the competition's connection with decreased harvest index due to inefficient resource use, as was documented in bean and wheat genotypes (Davis et al 1984;Pan et al 2003;Gebeyehu et al 2006). Pan et al (2003) pointed out that greater plant size hierarchy induced by competition implies a high incidence of growth redundancy which is detrimental to the yield performance of a crop population.…”

Rye–Vetch Mixture Proportion Tradeoffs: Cover Crop Productivity, Nitrogen Accumulation, and Weed Suppression

“…Decades of intercropping research have demonstrated that cereals are usually the dominant component in cereal–legume mixtures, suppressing the growth of the legume and contributing a greater proportion of biomass to the total mixture yield (Ofori and Stern, 1987). This competitive imbalance may be more severe for low‐growing legumes than for those with climbing growth habits (Davis et al, 1984; Fukai and Trenbath, 1993), but the performance of vetch in mixture with cereals still varies across studies. Kurdali et al (1996) and Tosti et al (2010) both saw reduced vetch dry matter productivity in a mixture with barley ( Hordeum vulgare L.), while Dhima et al (2007) also observed suppression of vetch by barley and oat ( Avena sativa L.) but not by wheat ( Triticum aestivum L.) or triticale (× Triticosecale Wittmack).…”

A compendium of crop varietal tolerance to weeds

“…The author suggested that this may be due to competition for light. (See CIAT [1980] or Davis et al [1984] for descriptions of growth habit types in beans.) Total weed growth was higher in 'Tara' plots (2560 vs. 2480 kg/ha for 'Great Northern 1140'); however, 'Tara' outyielded 'Great Northern 1140' under weed-free and weedy conditions.…”