Levels of Crotalaria juncea on growth, production, recovery and efficiency of the use of N in broccoli

Abstract

A lthough there are studies on nutrition and fertilizer recommendations for the commercial cultivation of broccoli (Brassica oleracea var. italica) and works with other types of organic fertilizers such as compost or manure (Oliveira et al., 2003;Yuri et al., 2004; Damato Junior et al., 2005), there are few studies on the effects of green manure on the growth and production of broccoli. The literature also lacks studies relating green manure doses to the production and/or growth of horticultural products.One of the few studies reports the influence of doses of organic compost (OC) on yield and quality of the "Ramoso Santana" broccoli seeds. Four compost rates (0, 30, 60, 90, and 120 t/ha) with 0.72% nitrogen and 40% organic matter were applied. The production of broccoli seeds (number and weight) per plant increased linearly with increased doses of OC (Magro et al., 2010 ABSTRACTThe recommendation for green manure (GM) in cropping systems still has little scientific support, with few studies addressing the effects of nutrient amounts from green manure on the growth and production of the crop. Our aim was to evaluate the effect of levels of Crotalaria juncea green manure on the growth, production, and efficiency of the use as well as the apparent recovery of N in broccoli crop. Seven treatments were established; the main with four doses of green manure: 0, 3, 6, and 9 t/ha on a dry matter (DM) basis, applied with 12 t/ha compost. The control treatments consisted of mineral fertilization, the treatment with 25 t/ha compost, and another as the absolute control. Comparatively, production under the absolute control was less than all other treatments with green manure doses and application of 12 t/ha compost. The production of plants grown with 25 t/ha compost was superior to that of plants grown with dose of 0 t/ha and similar to that obtained with 3 t/ha; however, it was inferior to those produced with doses of 6 and 9 t/ha green manure. The highest percentage of N recovered (REC N) by the broccoli plants was observed close to a dose of 3 t/ha green manure, with a maximum point of 37.90% (2.8 t/ha), while in larger doses of 6 and 9 t/ha showed estimated values of 31.91% and 20.49%, respectively. The physiological efficiency of the use of N (EFUN) showed an effect similar to apparent recovery of N (REC N), with higher EFUN from lowest to highest dose of green manure, that is, 3, 6, and 9 t/ha, with estimated values of 70.41, 62.45, and 26.02 g DM per g of N uptake, respectively. The mass amounts of applied C. juncea influenced positively on the growth and productivity of broccoli. The lower mass of applied green manure increases the physiological efficiency of the use of N with more apparent recovery of the applied N.Keywords: Brassica oleracea var. italica, green manure, nitrogen. RESUMO Doses de Crotalaria juncea no crescimento, produção, recuperação e eficiência de uso de N em brócolisA recomendação da adubação verde nos sistemas de cultivos ainda apresenta pouco suporte científico e poucos estudos abordam os ef...

Economic Analysis of Taro-Sunn Hemp Intercropping With Broccoli, Green Maize and Snow Pea as Successive Crops

“…For all the macronutrients evaluated, the values were higher in the treatments in which the cut of the sunn hemp occurred from the 145 DAS, demonstrating that it may have contributed to a higher productivity. A similar result was observed by Diniz et al (2017) when evaluating doses of Crotalaria juncea plus 25 t ha -1 of organic substrate. The authors verified that the application of 6 to 9 t ha -1 provided higher broccoli yield when compared to the application of 3 t ha -1 .…”

“…Vargas et al (2011) evaluated the influence of legume biomass on the production of cabbage in two successive crops. Diniz et al (2017), among other studies, evaluated the residual effect of Crotalaria juncea on the cultivation of zucchini and maize in sequence to broccoli.…”

Green Manure and Mineral Fertilization: Residual Effect on Dry Matter Production, Nutrient Extraction and Nutrients Recovery Efficiency in Two Succesive Crops

“…On the other hand, depending on the fertilizer type or fertilization dose used, the growth, yield and nutritional aspect of crops can change (Moreno-Cornejo et al, 2017), which generates different efficiency of utilization of the applied nutrients (Diniz et al, 2017b). In successive cropping systems, where short-cycle crops are used, the nutrients supplied through fertilization practices are not regularly absorbed by the first crop.…”

“…Therefore, the nutrients remaining in the soil can be used by other subsequent crops, which is known as the residual effect (REEF). The REEF on other crops depends on the characteristics of the soil, type of fertilizer used, fertilization dose, amount of nutrients that removed by the first crop and the amount of nutrients remaining in the soil (Båth et al, 2006;Diniz et al, 2017b). Although there are studies where the REEF of fertilization has been observed in subsequent crops, these studies have mainly focused on knowing the effect on the growth and yield of the plant (Diniz et al, 2017a), on the nutritional aspect (Båth et al, 2006) and the efficiency of nutrient recovery, specifically the N (Vargas et al, 2017).…”

Sample size for the estimation of Pearson’s linear correlation in crotalaria species

“…Crotalaria species, such as C. juncea, are used as cover plants in crop rotation systems with high production of fresh matter (Chaudhary, 2016) and nitrogen supply to the subsequent crops, positively influencing plant growth and productivity (Diniz et al, 2017;Elsaid & Silva, 2017). Other species of crotalaria, such as C. spectabilis, C. breviflora, and C. ochroleuca, can reduce the incidence or pest infestation, diseases and nematodes (Deberdt et al, 2015;Braz et al, 2016;Reigada et al, 2016).…”