Relações entre parâmetros de crescimento do fruto da manga cv. haden

Abstract

Um estudo realizado na maior região produtora e exportadora de manga no Nordeste brasileiro (Petrolina-PE) mostrou uma típica curva sigmoidal para o crescimento do fruto de manga cv. Haden. Além disso, um método não destrutivo para medições de crescimento do fruto foi estudado com base nas relações entre as massas seca e fresca, volume e o produto dos diâmetros do fruto de manga da cv. Haden. Os resultados mostraram que as massas seca e fresca podem ser estimadas a partir do volume do fruto calculado com base no produto dos seus diâmetros. Estudos de correlação mostraram coeficientes (r²) superiores a 0,91 para todas as épocas de avaliação ao longo do período de desenvolvimento do fruto, desde a floração plena à colheita. Foi também observado que déficit hídrico durante o crescimento do fruto reduz o acúmulo de massa seca do fruto, indicando que a prática da suspensão da irrigação, com o objetivo de adiantar a colheita e aumentar o teor de açucares do fruto, pode não ser vantajosa, uma vez que há uma redução da massa fresca do fruto.

Growth of champa fruit under agroecological conditions of Miraflores, Boyacá, Colombia

“…Thereafter, growth was again slow until 1489.1 GDD, reaching its maximum values at 6.47 ± 0.28 g and 1.37 ± 0.04 g for the fresh and dry mass, respectively (Figures 2 and 3). During this phase, the vacuoles shrank as storage compounds accumulated, and dry matter weight increased, while the seed development ended in a phase of preprogrammed desiccation characterized by a loss of fresh mass (Castro et al, 2004), however, this latter phase was not observed in champa fruit. Seeds represent 28% of fruit fresh mass and 32% of dry mass.…”

“…For the same zone (Miraflores, Boyacá), Balaguera et al (2009) reported a duration of 160 days. This considerable difference, according to Castro Neto & Reinhardt (2003), may be attributed to variations in the plant growth cycle and, consequently, to the length of the reproductive and fruit growth periods. This effect highlights the importance of expressing the growth and development of champa fruit in terms of physiological time, given that in the tropics, temperature is the environmental variable that exerts the most influence on crop development by its action on the enzymatic reactions that directly or indirectly mediate the developmental processes (Normand & Léchaudel, 2006).…”

“…Castro Neto & Reinhardt (2003) stated that the accumulation of dry mass might be a consequence of the higher contribution of photosynthesis associated with the translocation of dry matter from other parts of the plant to the fruit, with the remobilization of previously photosynthesized photoassimilates accounting for 40 to 50% of the fruit weight.…”

“…These masses were notably low until 999.4 GDD (Figures 2 and 3), coinciding with a gradual increase in the AGR and a stable behavior of the RGR. According to Castro et al (2004), this phase corresponds to cell division, and during this stage, the histodifferentiation and morphogenesis of the seed accompany extensive cell divisions by the unicellular zygote, with the resulting cells differentiating to form the embryo. The second phase of development was that of accelerated growth ending at 1422.8 GDD (138 DAF), a phase characterized by the accumulation of both endosperm reserves and water (Castro et al, 2004).…”

“…According to Castro et al (2004), this phase corresponds to cell division, and during this stage, the histodifferentiation and morphogenesis of the seed accompany extensive cell divisions by the unicellular zygote, with the resulting cells differentiating to form the embryo. The second phase of development was that of accelerated growth ending at 1422.8 GDD (138 DAF), a phase characterized by the accumulation of both endosperm reserves and water (Castro et al, 2004). During this phase, the AGR reached its highest point (1248.19 GDD) with 0.0033 g GDD, and the RGR showed its greatest decrease (Figure 3).…”