RESUMO:O trabalho teve como objetivos determinar a evapotranspiração da cultura (ETc) e o coeficiente da cultura (Kc) para o mamoeiro (Carica papaya L.). O experimento foi realizado na área de convênio UENF/PESAGRO-RIO, no município de Campos dos Goytacazes -RJ, no período de 25-4-2006 a 20-8-2007, utilizando PALAVRAS-CHAVE:Carica papaya L., consumo hídrico, irrigação, manejo. EVAPOTRANSPIRATION AND CROP COEFFICIENT OF PAPAYAABSTRACT: This study aimed to determine the crop evapotranspiration (ETc) and the crop coefficient (Kc) for of UENF/CALIMAN01 papaya hybrid (Carica papaya L.). The experiment was conducted in an area of UENF/PESAGRO-RIO, in Campos dos Goytacazes, RJ, Brazil, from 4-25-2006 to 8-20-2007. To determine the ETc and Kc, a weighing lysimeter (6 m 2 ) was used. The reference evapotranspiration (ETo) was determined by the Penmam-Monteith (FAO) method. The maximum crop evapotranspiration was of 2.9 mm day -1 , 229 days after the transplant (DAT), and the medium crop evapotranspiration during the experiment was of 1.8 mm day -1 . The value of crop coefficient (Kc) varied linearly from 0.63 to 1.05, the transplant to 206 DAT. After this period, the variation of Kc presented inversely relation with the canopy diameter, being reduced to a value medium minimum of 0.81, to 300 DAT. Considering the whole period of study, it was obtained an average Kc of 0.87.

Leaf area estimation is an important feature in physiological research involving predominantly photosynthesis, transpiration and growth. This study was carried out to develop a practical and nondestructive empirical mathematical model to estimate the area of one leaf and the total leaf area for papaya trees (Carica papaya L.). Two irrigated commercial orchards were evaluated over a period of 50 to 550 days after transplanting, during which the length of the leaf midrib (LM) varied from 0.04 to 0.60 m. A mathematical model was developed to estimate the area of one leaf for the papaya tree, taking into account LM and the age of the plant measured in days after transplanting. The model was considered satisfactory. Based on the average length of the last two leaves of the crown and the total leaf number of the plant, it was possible to satisfactorily estimate the total leaf area of the papaya tree. Key words: Carica papaya L., papaya, model, leaf architecture, biometry ÁREA FOLIAR TOTAL DO MAMOEIRO ESTIMADA POR UM MÉTODO NÃO-DESTRUTIVORESUMO: A estimativa da área foliar é importante no estudo de aspectos fisiológicos que envolvam, principalmente, crescimento, transpiração e fotossíntese. Desenvolveu-se um modelo matemático empírico prático e não-destrutivo para estimativa da área de uma folha e a área foliar total do mamoeiro (Carica papaya L.) em pomar comercial. Para isso foram avaliados dois pomares irrigados. As plantas foram avaliadas no período de 50 a 550 dias após o transplantio, em que as folhas tiveram o comprimento da nervura central (LM) variando de 0,04 m a 0,60 m. Um modelo matemático foi desenvolvido para a estimativa da área de uma folha do mamoeiro, levando em consideração o LM e a idade da planta, representada em dias após o transplantio. O modelo foi considerado satisfatório. Com base no comprimento médio das duas ultimas folhas da copa e do número total de folhas presentes na planta pode-se estimar a área foliar total do mamoeiro.

No abstract

Leaf area has significant effect on tree transpiration, and its measurement is important to many study areas. This work aimed at developing a non-destructive, practical, and empirical method to estimate the total leaf area of green dwarf coconut palms (Cocos nucifera L.) in plantations located at the northern region of Rio de Janeiro state, Brazil. A mathematical model was developed to estimate total leaf area values (TLA) as function of the average lengths of the last three leaf raquis (LR3), and of the number of leaves in the canopy (NL). The model has satisfactory degree of accuracy for agricultural engineering purposes.

RESUMOTeve-se como objetivo neste trabalho, determinar o coeficiente de resposta ao déficit hídrico na produção de frutos comerciais e totais do mamoeiro, cultivado na região Norte do Estado do Rio de Janeiro. O experimento foi realizado na área de convênio UENF/PESAGRO-RIO, no município de Campos dos Goytacazes, RJ, no período de 25/04/2006 a 18/05/2007, utilizando-se o mamoeiro cultivar Híbrido UENF/CALIMAN01 e um delineamento em blocos casualizados, com cinco tratamentos, correspondendo às reposições de 50% (T1), 75% (T2), 100% (T3), 125% (T4) e 150% (T5) da evapotranspiração de referência (ETo), com quatro repetições. A máxima produção comercial real da cultura, aos 13 meses de cultivo e com quatro meses de colheita, foi de 38,78 t ha -1 (T3) e a máxima produção total real encontrada foi de 49,42 t ha -1 (T5). O mamoeiro cultivar Híbrido UENF/CALIMAN01 conduzido até os 13 meses de cultivo e com quatro meses de colheita, apresentou um coeficiente de resposta de produção (ky) para frutos comerciais de 1,4581 e para produção total um coeficiente igual a 0,5674. Palavras-chave: Carica papaya L., coeficientes de sensibilidade, deficiência hídricaResponse coefficient of papaya yield to water stress (ky) in Northern Rio de Janeiro ABSTRACTThe objective of this study was to determine the response coefficient to water stress in the commercial and total yield of papaya fruits grown in the northern region of the State of Rio de Janeiro. The experiment was conducted in an area of UENF/PESAGRO-RIO in the municipality of Campos dos Goytacazes, Rio de Janeiro, from 25/04/2006 to 18/05/2007, using the papaya cultivar Hybrid UENF/CALIMAN01. The experiment had a randomized block design with five treatments [replacement of reference evapotranspiration (ETo) by 50% (T1), 75% (T2), 100% (T3), 125% (T4) and 150% (T5)], with four replications. The highest real commercial yield of the crop after 13 months of growth and four harvest months was 38.78 t ha -1 (T3) and the highest total real yield was 49.42 t ha -1 (T5). After 13 months of growth and 4 harvest months of the papaya cultivar Hybrid UENF/CALIMAN01 the response coefficient for commercial fruit yield (ky) was 1.4581 and 0.5674 for total yield.

No abstract

The objective of this study was to obtain mathematical models to estimate non-destructively the fruit mass of pear cv. ‘Triunfo’. To this end, 128 fruits from all developmental stages collected at three different times were used. Fruits were measured for maximum length (L), maximum width (W) and observed mass (OM). For the adjustment, with a sample of 100 fruits, the models first degree linear, quadratic and power were tested, in which the OM was used as the dependent variable in function of L and W. From a sample of 28 fruits, separated for this purpose the equations were validated. Thus, it indicates an equation of the quadratic model represented by EM = 36.020218 – 3.067232(W) + 0.082568(W)2  using from the measurement of the largest fruit width (W), as the most accurate to estimate the fruit mass of pear cv. ‘Triunfo’.

No abstract