Most commercial papaya varieties segregate hermaphrodite and female plants. Growers normally select hermaphrodite plants in the field, due to market preferences. This requires planting multiple plants per site and later thinning of the females, distinguished by flower bud inspection. Micropropagation or the use of molecular markers are two possibilities to grow only hermaphrodite plants. Under the tropical conditions of this study, the field performance of hermaphrodite papaya plants developed by both of these methods was described. Moreover, a multiplex qPCR reaction was optimized. Hermaphrodite seedlings selected by molecular markers and plants obtained by micropropagation, had a lower slenderness ratio and initiated fruit production at a lower height than those selected by the conventional practice of the orchard. An analysis of flower types between the sex determination methods indicated that growing one hermaphrodite papaya plant per hole reduces the percentage of female-sterile flowers, resulting in fruit set at a lower trunk height and higher yields.
En un cultivo, una nueva variedad, obliga a implementar o ajustar técnicas de producción que complementen las bondades del mismo. En pejibaye se tiene al menos un nuevo material sin espinas con gran potencial para producción de palmito (Mora et al. 1999 RESUMENDistancias de siembra y combate de malezas en pejibaye (Bactris gasipaes K.) para palmito: efecto en el suelo y artrópodos. En la Estación Experimental Los Diamantes, ubicada en Guápiles, Costa Rica, se evaluó, entre los años 2000 y 2001, el efecto de cuatro distancias de siembra entre plantas y dos estrategias de control de malezas, sobre variables químicas y microbiológicas del suelo, población de insectos y malezas, asociados al cultivo de pejibaye para palmito. No se observaron diferencias entre tratamientos con respecto a los nutrimentos del suelo, con excepción de una mayor cantidad de K en las parcelas con combate físico en el segundo muestreo. Hubo cambios entre muestreos para variables como el pH, Al y Ca. En el segundo muestreo las cantidades de hongos, bacterias y actinos en el suelo, fueron diferentes entre tratamientos. En un bloque adicional de parcelas de palmito con malezas, se recolectaron un total de 65 familias de insectos. Hubo aumentos importantes en el número de morfoespecies y de individuos entre el primero y segundo muestreo en familias de insectos; el mayor incremento en el número de familias, morfoespecies y número de individuos se dio en las parcelas sembradas a 0,25 m entre plantas. ABSTRACTWeeds control in peach palm (Bactris gasipaes K.) for palm hearts: effect on soil and arthropods. A study was conducted at Los Diamantes Experiment Station, located in Guápiles, Costa Rica during the 2000 and 2001 year, to compare the effects of four sowing densities of spineless "palmito" peachpalm and two weed management strategies (chemical and physical) on chemical and microbiological characteristics of the soil, insect and weed populations in this crop. No differences were observed among treatments in regard to soil nutriments, except for a larger quantity of K in the plots subjected to physical treatment in the second sampling. Changes among samplings (first an second) were evident for variables such as the pH, Al and Ca. In the second sampling the quantities of fungi, bacteria and actynomycetes in the soil, were different among treatments. In additional plots with overgrowth, a total of 65 families of insects were gathered. There were important increases in the number of morphospecies and of individuals between the first one and second sampling in families of insects; the largest increment in the number of families, morphospecies and number of individuals was found in plots sowed with 0,25 m distance among plants.
Storey (1953) sugiere que la identidad sexual de la papaya está dada por una serie de genes fuertemente ligados que se heredan como un solo locus. Estos genes codificarían para caracteres sexuales tales como presencia/ausencia de estambres, presencia/ausencia de ovario,
Carpellody is a phenomenon that affects hermaphrodite flowers of papaya, and consists in the transformation of the stamens into additional carpels, resulting in ovary malformation that consequently affects fruit shape and diminishes its market value. The objective of this study was to quantify the incidence of flower carpellody in papaya, and the effect of temperature on this phenomenon. An experiment was carried out between October of 2006 and January of 2007 at ”Los Diamantes” Agricultural Experiment Station, located in the province of Limón. Four breeding lines and four experimental hybrids were arranged in a randomized complete block design with four replications. The analyzed variables were the carpel number for ovaries of hermaphrodite flowers and the daily temperature during a 60-day period prior to floral anthesis of each evaluated flower. The carpel number of lines and hybrids differed significantly each week (p≤0,03). Line and hybrid averages also differed significantly during the twelve-week period (p<0,0001). The cross between a strong carpellodic line and a stable or a weak female-sterile line resulted in a hybrid that exhibited carpellody, which suggests that carpellody is dominant. The correlation between carpel number and temperature suggests that the amplitude of temperature fluctuations during the day was a determinant factor in the induction of carpellody.
La guayaba (Psidium guajava) ha sido la especie de Psidium más desarrollada para el consumo de su fruta, en contraste con el güísaro (Psidium guineense), una especie que posee similitudes importantes con la guayaba. El objetivo de este trabajo fue medir algunas características en la planta y en la fruta de cuatro híbridos entre las especies Psidium guajava y Psidium guineense. El experimento se realizó en la Estación Experimental Los Diamantes, ubicada en el cantón de Pococí, Provincia de Limón, Costa Rica. Los tratamientos evaluados fueron cuatro híbridos, distribuidos en un diseño de bloques completos al azar con cuatro repeticiones. Las variables evaluadas en la planta fueron altura, número de ramas, diámetro de copa, número de flores y frutos. En los frutos se evaluó peso, sólidos solubles, pH y número de semillas. No hubo diferencias entre los híbridos para altura de planta (p=0,81), diámetro de la copa (p=0,37) ni en el número de ramas principales (p=0,55). Las plantas híbridas fueron similares al güísaro con respecto a su arquitectura y el peso de la fruta. Las diferencias en el número de flores por planta (p=0,03), número de frutos por planta (p=0,02) y el número de semillas por fruto (p=0,004), se estableció principalmente entre el híbrido de guayaba triploide por güísaro con respecto a los demás híbridos.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.