Effect of Competition on the Interaction Between Maize and Weed Exposed to Water Deficiency

Abstract

The ability of plants to adapt to water deficient conditions in soil is directly related to the competitive ability of each species. The objective of the present study was to evaluate the effects of water deficiency and interspecific competition on the growth components of maize (Zea mays), brachiaria (Urochloa decumbens), and hairy beggarticks (Bidens pilosa L). The experimental design was in randomized blocks, with eight replications. The treatments were arranged in a 5 × 2 factorial design, with the first factor corresponding to the different competitive arrangements among species (maize + U. decumbens, maize + B. pilosa, maize without competition, U. decumbens without competition, and B. pilosa without competition). The second factor constituted two water regimes (daily irrigation and water deficit). The soil water deficient condition strongly decreased maize plant growth; however, it had little or no effect on the growth of weeds U. decumbens and B. pilosa. Interspecific competition decreased the growth of maize plants and U. decumbens, and intensified the negative effects of water deficiency on these species. Interspecific competition and water deficiency also decreased the N, P, and K content in maize plants, which contributed to the effects on plant growth. U. decumbens was more competitive with maize compared to B. pilosa.

WATER DEFICIT ON GROWTH AND PHYSIOLOGICAL INDICATORS OF Bidens pilosa L. AND Bidens subalternans DC.

“…The reduction of stomatal conductance causes lower transpiration and, consequently, lower water loss, causing higher plant tolerance to water stress (DUTRA et al, 2015). This mechanism is an essential defense strategy, especially in semi-arid regions, where long periods occur without the occurrence of high-temperature rains (FREITAS et al, 2017;FREITAS et al, 2019).…”

“…Easy dispersion and high seed production capacity allow both B. pilosa and B. subalternans to colonize cultivated and noncultivated areas (PAMPLONA et al, 2020). In addition, these species have a great capacity to extract water and nutrients from the soil, making these species good competitors for growth resources, during various crop cycles (SANTOS et al, 2015;FREITAS et al, 2019;SOARES et al, 2019). According to Deiss et al (2017), losses of productivity in the range of 30% in the soybean crop occurred due to the interference of B. pilosa and B. subalternans.…”

Water deficit and plant recovery affect interaction between soybean and slender amaranth

“…Moreover, the authors observed that shoot dry matter of rye decreased by 37, 47 and 33% in water deficit conditions with interspecific and intraspecific competition, respectively. Freitas et al (2019) reported that there was competition for resources among maize, black-jack (Bidens pilosa) and signal grass (Urochloa decumbens), even when the amount of water in the soil was close to the field capacity. A decrease in growth due to either intra or interspecific competition results from spatial competition among plants.…”

“…on redroot pigweed depended on plant density; the larger the number of plants, the higher the shoot dry matter of the weed. Freitas et al (2019) showed that interspecific competition decreased the growth of corn and signal grass (Urochloa decumbens) plants and intensified negative effects of water deficit on these species.…”

Interference of horse purslane (Trianthema portulacastrum L.) and other weeds affect yield of autumn planted maize (Zea mays L.)

“…Allelopathic chemicals restrict the crop growth and development of cereal crops ( Zea mays ) by producing phytotoxic chemicals ( Bhatt et al, 2001 ). Crop growth and development mainly depends on weed crop competition period, as competition period prolonged, it adversely influenced growth and development of crop ( Freitas et al, 2019 ). Durational interference of weeds significantly influences crop yield attributes as well as crop productivity ( Yaghoobi and Siyami, 2008 ).…”