Effect of Vacuum Cooling on Shelf Life of Organic Chayote Shoot （Sechium edule Sm.）

The effect of vacuum cooling on shelf life of organic chayote was investigated. Vacuum cooling processes of organic chayote shoot packed in perforated polyethylene package using different vacuum pressure reserving operation modes were experimented. The holding final pressures for vacuum-cooled organic cilantro packed in holed polyethylene bags were set at two different levels, namely at 10 and 11 millibar. The pressures were experimented with 3 levels of reserving time of 3, 4 and 5 minutes. The weight loss percentage of chayote shoot during precooling to the temperature of 8 ~ 1 ~C using reserving pressure of 10 milibars for 3, 4, and 5 minutes were 0.5, 0.7, and 0.9, respectively. For the weight loss percentage during precooling using reserving pressure of 11 milibars for 3, 4, and 5 minutes were 0.4, 0.5, and 0.5, respectively. The optimum parameter for vacuum cooling process of organic chayote shoot at the initial temperature of 19-23 ℃to 8 ±1 ℃was the reserving pressure of 11 mbar with reserving time of 5 minutes. The precooled organic chayote shoot was then stored at 8 ℃ for quality analysis. The results showed that vacuum cooling had no effect on the change of color, chlorophyll a, b and total chlorophyll. However, precooled organic chayote shoots showed better appearance than non-precooled vegetables. Vacuum cooling can reduce weight loss percentage. The amount of total soluble solids in organic chayote shoots increased with storage time. Precooled organic chayote shoot had longer shelf life of 8 days compared to normal storage life of 5 days.

Avocado and Chayote-Two Edible and Medicinal Plants

There are two agricultural products originating in Mexico with nutritional,medicinal and cosmetic properties.One is the Avocado,the fruit of a tree that is widely accepted in the Mexican diet due to its pleasant flavor.The other is the Chayote,a green vegetable that grows like a vine,with guides that can exceed up to 6 m in length.These two foods,in addition to being consumed nationally,are also exported,which is why they are of economic importance for Mexico.Avocado is the most exported,after coffee and tomato,with Chayote in fourth place.

The Cytological Studies on Neglected and Underutilized Cucurbit Species with Special Reference to Chayote,an Under-Exploited Species

Cucurbitaceae family contains important economic and medical crops, they can be divided into two categories according to the worldwide consumption, use, and production. The Cucurbit Popular Crops (CuPoC) are comprised of cucumber, the Cucurbita group (pumpkin and squash), melon and watermelon. On the other hand, Neglected and Underutilized Cucurbit Species (NUCuS) group has been used as food sources, medicinal properties and elements in the elaboration of different types of items. The NUCuS is represented in this review work by bitter gourd, bottle gourd, chayote, ridge gourd, and snake gourd, which are recognized mainly in Asia. The center of origin of the majority of NUCuS was proposed to be in the Old World. In contrast, the origin of chayote or Sechiumedule (Jacq.) Sw. was suggested in the New World, precisely in Mesoamerican region based on linguistic uses and distribution of wild relatives. The environmental factors along with artificial selection, production systems and traditional knowledge have been influenced the evolutionary history of NUCuS, Infraspecific variation of chayote has been reported in Mexico over-described varietal groups. These descriptors were determined based on biochemical and morpho-structural traits;however, cytogenetic analyses are scarce. Specifically, chromosome and nuclear content analyses are important to support botanical groups, analyze artificial selection history, developing breeding and conservation programs. The present review paper discusses agronomic and evolutionary importance based on cytological evidence in NUCuS, mainly in the prominent chayote;with the perspective to prompt breeding, conservation, cytology, structural and functional genomics research for its sustainable utilization.

Isolation and Characterization of Novel Microsatellite Markers in Chayote[Sechium edule(Jacq.)Sw.]

Chayote [Sechium edule (Jacq.) Sw.] is an economically important species in Latin America;however, there are very few reports available regarding its genetic diversity. Out of 11 microsatellite markers isolated, 10 loci provided 1 to 7 alleles per locus in a set of Mexican chayote accessions. Observed and expected heterozygosities for each locus ranged from 0.00 to 0.85 and 0.00 to 0.73, respectively. The overall genetic diversity detected by microsatellites was compared with that detected by P450-based analogue markers, a genome-wide dominant marker. Genetic diversity values obtained by the newly designed microsatellite markers were almost equal to the value estimated by PBA markers, but genetic distances calculated by both marker systems were not significantly correlated. Additional microsatellite markers, which could detect more polymorphisms, may be necessary to analyze the genetic diversity and structure of Mexican chayote collections.