Bean cultivation in a subsistence farming system in the northeast of São Paulo state - Brazil

Abstract

The colonization of the State of São Paulo, Brazil of the northeastern region, is related to historical movements, such as "tropeirismo" (séc. XVIII and XIX) and Italian immigration (séc. XIX). The agriculture presently practices used by farmers descendent of immigrants does not differ from the techniques used at the beginning of the century. In the Cunha region of the Atlantic Rain Forest ecosystem poor bean yield associated with low fertilizer input, plant disease and soil erosion led to slash-and-burn farming. This work is an attempt at identifying sustainable farming practices that would minimize bean disease and maximize nitrogen assimilation. For that purpose soil fertility and plant cultivar were studied under standard agronomic practices to determine their effect on seed yield, total nitrogen of grain and number of root nodules. Fertilization, liming and molybdenum from 16 sites increased yield by 342% and 369% for the landrace 'Serro Azul' and commercial variety 'Carioca 80 SH', respectively. In addition, plants grown with fertilizer presented more nodules and more nitrogen in grain per hectare. The increase of crop yield per hectare might increment the family income and reduce deforestation of the Atlantic forest. Key words: Phaseolus vulgaris, Rhizobium tropici, landrace, lime, molybdenum CULTIVO DO FEIJOEIRO SOB CONDIÇÕES DE SUBSISTÊNCIA NO NORDESTE DO ESTADO DE SÃO PAULO-BRASILRESUMO: A história de colonização da região do Alto Vale do Paraíba está relacionada a movimentos históricos como tropeirismo (sec. XVIII e XIX) e imigração Italiana (séc. XIX). As práticas de agricultura utilizadas pelos agricultores atuais são as mesmas utilizadas desde o início do século, e muitos dos materiais cultivados atualmente, como algumas cultivares de feijão e milho, foram trazidas pelos tropeiros em suas viagens entre Minas Gerais e Paratí. O cultivo do feijoeiro no Município de Cunha -São Paulo é caracterizado pelo baixo rendimento resultante do reduzido uso de insumos, doenças endêmicas e práticas de preparo de solo não apropriadas em áreas de topografia acidentada. Com o objetivo de identificar práticas de cultivo adequadas e maximizar a absorção do nitrogênio, foi instalado um conjunto de experimentos onde avaliaram-se o rendimento de grãos, teor de nitrogênio nos grãos e número de nódulos. A calagem e adubação mineral em 16 locais foram suficientes para aumentar o rendimento de grãos em 342% e 369% para a cultivar "crioula" Serro Azul e comercial Carioca 80 SH, respectivamente, com significativo aumento da nodulação e nitrogênio nos grãos em quantidades totais. Maior rendimento por hectare significa acréscimo na renda familiar e redução da pressão sobre as áreas de floresta remanescente (Mata Atlântica).

Genetic Variation of Landraces of Common Bean Varying for Seed Coat Glossiness and Disease Resistance: Valuable Resources for Conservation and Breeding

“…It has been subjected to many diseases, such as anthracnose, and pests. De Oliveira et al [11] and De Oliveira and Tsai [13] showed low yield from this variety from experiments performed at different farms in Cunha, SP, when no fertilizer was applied. This treatment represented the traditional way that farmers cultivated this landrace at their farms.…”

“…This treatment represented the traditional way that farmers cultivated this landrace at their farms. However, when a sort of fertilizer treatments were applied in soil cultivated with this variety, along with one commercial standard at the time (IAC-Carioca 80SH), the yield was significantly improved from around 930 kg ha −1 (without fertilizer) to 1360 kg ha −1 (fertilizer application along with lime and foliar spray of molybdenum) [13].…”

“…Usually, in the case of landraces, where local selection has been performed, it is more frequent to find common bean accessions that show glossy seed coat [24] (checking the list of genotypes) than in breeding programs. In the case of the landrace Serro Azul, both variants Serro Azul Brilhante (glossy) and Serro Azul Fosco (opaque) have been cultivated [11,13].…”

“…Serro Azul shows considerable morphological variability, revealing different types of seeds. It shows high genetic variation for seed colors and patterns [12], disease and insect resistance and nodulation ability [11,13], which are among the main aspect studies in breeding programs of common bean.…”