Weed management in sorghum-legume intercropping systems

Barman

Conservation Agriculture

et al. 2014

Conservation agriculture (CA) does have several advantages over conventional tillage (CT)-based agriculture in terms of soil health parameters. However, weeds are the major biotic constraint in CA, posing as a great challenge towards its adoption. The presence of weed seeds on the upper soil surface, due to no tillage operation, leads to higher weed infestation in CA, and so far, herbicides are the only answer to deal with this problem. Overreliance of herbicide use showed its consequence in terms of environmental pollution, weed shift and herbicide resistance development in weeds. Growing herbicide-tolerant crops using nonselective herbicides could be a broad-spectrum weed management technique to tackle weed shift, but the same is being resulted in the evolution of more problematic 'super weed'. These observations indicate the need of integrated weed management technologies involving the time tested cultural practices, viz. competitive crop cultivars, mulches, cover crops, intercrops with allelopathic potential, crop diversification, planting geometry, efficient nutrient, water management, etc., along with limited and site-specific herbicide application. The modern seeding equipment, e.g. 'Happy Seeder' technology, that helps in managing weeds through retention of crop residues as mulches, besides providing efficient seeding and fertilizer placement, shows the promise of becoming an integral part of CA system.

Section: Intercroppingmentioning

confidence: 99%

Weed Management in Conservation Agriculture Systems

Barman

Conservation Agriculture

et al. 2014

“…Some observed advantages have been high yield potential along with resilience to weather aberrations and efficient utilization of resources (Francis 1981), with low yield variability from season to season and less susceptibility to disease (Newton and Thomas 1992). Weed pressure may be reduced (Abraham and Singh 1984), with reduced competition for growth resources, which can result in higher crop yields. Raper and Barber (1970) and Baldwin et al (1972) reported that root systems of different cultivars of a crop mixture may exploit different layers of the soil and tap more water than either cultivar in monocrop.…”

mentioning

confidence: 99%

Mixture performance of phenotypically contrasting barley cultivars

Essah

Stoskopf²

2002

Can. J. Plant Sci.

Essah, S. Y. C. and Stoskopf, N. C. 2002. Mixture performance of phenotypically contrasting barley cultivars. Can. J. Plant Sci. 82: 1-6. There is lack of information on the yield and yield component performance of same-row and alternate-row mixtures (SRM and ARM) of widely contrasting barley (Hordeum vulgare L.) phenotypes. Therefore, four phenotypically contrasting spring barley cultivars, each selected to represent a unique combination of spike type (two-row or six-row), height (short or tall) and days to maturity (early or late) were used in 1991 and 1992 in field experiments at the Elora Research Station in Ontario, Canada, with the objective of determining whether a yield and/or yield-component advantage could be associated with same-row or alternate-row mixtures of barley cultivars. The four cultivars chosen for the study were each grown as monocrops, and in all six possible binary (two-cultivar) mixture combinations as same-row or alternate-row mixtures, in a randomized complete block design. A 13% yield increase of early, short:late, tall SRM over the midcomponent (weighted mean of the components grown in monocrop) yield in 1991, and 14% yield increase of early, tall:late, tall SRM over the midcomponent yield in 1992 was observed. Between the 2 yr, cultivars in ARM produced similar or significantly greater yields than the monocrop yields, except in 1991, when the late, short cultivar in ARM with early, tall cultivar produced significantly lower yields than in monocrop. The spike number m -2 was similar for all mixtures and their midcomponents, except in 1992, when early, short:late, short in ARM produced 7.0% more spikes than the midcomponent. The results of this study indicate a possible yield advantage of phenotypically contrasting barley mixtures compared to monocrops, with early, short:late,tall and early, tall:late, tall in same-row mixtures having the best combining abilities. . L'objectif était de voir s'il y a un lien entre l'amélioration du rendement et/ou des composantes du rendement et la culture du mélange dans le même rang ou en rang alternés. Les quatre variétés retenues ont chacune été cultivées seules et dans les six permutations binaires (deux cultivars) possibles, dans le même rang ou en rangs alternés, lors d'un essai en blocs aléatoires complets. En 1991, les chercheurs ont noté une hausse de 13 % du rendement pour le mélange hâtif, nain:tardif, élevé cultivé dans le même rang, comparativement à la moyenne pondérée des composantes du rendement pour les monocultures. L'année suivante, ils ont observé une hausse de 14 % pour la combinaison hâtif, nain:tardif, élevé également cultivée dans le même rang. D'une année à l'autre, les mélanges cultivés en rangs alternés ont donné un rendement semblable ou sensiblement plus élevé que les monocultures, sauf en 1991, où la variété tardive, naine cultivée en rangs alternés avec le cultivar hâtif, élevé a enregistré un rendement sensiblement plus faible que la monoculture. Le nombre d'épis par mètre carré pour toutes les combinaisons était simila...

“…In contrast to the results for maize, bean leaves per plant, as well as plant height, leaf area, branch number per plant, pods per plant and dry weight had higher mean values (significant or not significant) under weedy conditions, but bean grain yield, bean 100-grain weight and bean grains per pod were higher under weed-free conditions. Maybe these results for bean relate to interspecies competition between bean and weeds for nutrients and water uptake, which caused higher growth rates of bean plants under conditions of no weed control (Abraham and Singh 1984).…”

Section: Discussionmentioning

confidence: 99%

“…Their study showed that intercropping can use soil resources more efficiently. In the study of Abraham and Singh (1984) intercropping of legumes increased growth, uptake of N, P and K and yield of sorghum compared to sole cropping of sorghum.…”

Section: Fig 1 Maize and Bean Land Equivalent Ratio (Ler) As Affectmentioning

confidence: 99%

Effect of plant density ratios and weed control on the performance of maize-bean intercropping

Sadeghi¹,

Kazemeini²,

Edalat³

2012

J. Ecol. Environ.

A 2-year study (2010)(2011) was carried out in order to evaluate the effects of bean and maize intercropping. The experiment tested five different cropping systems: sole cropping of each crop, as well as intercropping of maize/bean with the ratios of 1:3 (M 1 B 3 ), 2:2 (M 2 B 2 ) and 3:1 (M 3 B 1 ), each of which took place in the presence of two weed management systems (no weed control and weed eradication through manual removal), in a factorial experiment based on randomized complete block design using three replicates. Tests of homogeneity of variance for combined data over two years showed that data of both years could be analyzed together. The results showed that the effect of intercropping treatments on all measured traits in maize and bean were significantly different. A minimum land equivalent ratio (LER) for maize (0.78) was obtained for M 3 B 1 under conditions of no weed control, while the highest LER (1.03) was observed in M 3 B 1 under weed-free conditions. The highest (0.99) and lowest (0.70) LER values for beans were recorded for M 1 B 3 under weed-free conditions and M 3 B 1 under conditions of no weed control, respectively. M 1 B 3 under weed-free conditions showed the highest total LER (2.02), while M 3 B 1 under conditions of no weed control showed the lowest (1.48). Results of this study indicated that intercropping bean and maize can be an effective method to increase total productivity, and that the M 1 B 3 system was the best cropping system for high productivity.