Made available in DSpace on 2017-07-25T19:29:42Z (GMT). No. of bitstreams: 1 priscilac.pdf: 444720 bytes, checksum: c7c97a2669211c430c6c6d5f54d26ee6 (MD5) Previous issue date: 2006-12-13 / The experiments were carried out in an experimental area of the Ponta Grossa State University, Parana State, Brazil in winter (experiment 1) and spring (experiment 2) of 2005/2006, with the aim to evaluate the production of two crisphead lettuce (Lucy Brown and Raider Plus) under five different environments of culture: thermo-reflective screen (Aluminet 40%), diffusive screen (ChromatiNet 40%), natural environment, low tunnel with polyethylene and under nonwowen protection (white polypropylene of 17 g/m2 grid). The experimental design for both experiments was a completely randomized with four replications in a factorial scheme 5x2 (crop systems x cultivars). For both the experiments where evaluated: the total, commercial head and outer leaves fresh matter weight (BFT, BFCab and BFS- g/m2), and the outer leaves as well as their total and marbetable head dry matter (BST and BSCab - g/m2). For experiment 2 dry matter of the outer leaves, index of the foliar area of the outer leaves (IAFS) and of the leaves of the commercial head (IAFCab) were also evaluated. In the winter of Ponta Grossa, for both the cultivars, the crop systems qith nonwowen protection and low tunnel it had an early harvest of 21 days. However, in the spring, did not have difference in the cycle of the lettuce, independent of the cultivar and the crop system. But, the commercial production were superior in relation to the winter, possibly because of the more favorable climatic conditions for the crisphead lettuce culture. Keywords: Lactuca sativa, cultivars, protected cultivation, tunnel, polypropylene, Aluminet, ChromatiNet / Estadual de Ponta Grossa, no inverno (experimento 1) e primavera (experimento 2) de 2005/2006, com objetivo de avaliar a produção de duas cultivares de alface americana (Lucy Brown e Raider Plus) sob cinco ambientes de cultivo: malha termorefletora (Aluminet 40%), malha difusora (ChromatiNet 40%), ambiente natural, túnel baixo com polietileno e agrotêxtil branco (17 g/m2 de gramatura). O delineamento experimental para ambos os experimentos foi inteiramente casualizado, distribuídos em esquema fatorial 5x2 (sistemas de cultivo x cultivares) com quatro repetições. Para ambos os experimentos avaliaram-se: biomassa fresca total (BFT), biomassa fresca da cabeça comercial (BFCab), biomassa fresca das folhas da “saia” (BFS), biomassa seca da cabeça comercial (BSCab) e biomassa seca total (BST). Para o experimento 2 avaliou-se também biomassa seca das folhas da saia (BSS), índice de área foliar das folhas da “saia” (IAFS) e das folhas da cabeça comercial (IAFCab). No inverno de Ponta Grossa, para ambas as cultivares, os sistemas de cultivo com agrotêxtil e túnel apresentaram precocidade de 21 dias na colheita. Entretanto, na primavera, não houve diferença entre o ciclo da alface, independente da cultivar e do ambiente de cultivo. Porém, a produção comercial foi superior em relação ao inverno, possivelmente devido às condições climáticas mais favoráveis a cultura da alface americana.

Thesis--Auburn University, 2010. / Abstract. Includes bibliographic references