Resposta da maçã cv. Fuji ao etileno no armazenamento em atmosfera controlada Response of Fuji apples to ethylene in controlled atmosphere storage

Conduziu-se um experimento com o objetivo de avaliar o efeito das concentrações de etileno sobre a manutenção da qualidade e ocorrência de distúrbios fisiológicos na maçã cv. Fuji armazenada em atmosfera controlada (AC) com 1kPa de O2 e 0,2kPa de CO2 na temperatura de 0,5ºC. O delineamento experimental foi o inteiramente casualizado com três repetições. Os tratamentos avaliados foram: 0,25; 20; e, 800<FONT FACE=Symbol>m<img src="http:/img/fbpe/cr/v31n6/a05img01.gif" BORDER=0></FONT>.L-1 de etileno. As avaliações foram realizadas após nove meses de armazenamento, no momento da abertura das câmaras e após sete dias de exposição a 25ºC. Somente os frutos mantidos em 800<FONT FACE=Symbol>m<img src="http:/img/fbpe/cr/v31n6/a05img01.gif" BORDER=0></FONT>.L-1 de etileno durante o período de conservação em AC foram influenciados pelo etileno, apresentando maior respiração e síntese de etileno, menor firmeza de polpa e cor de fundo da epiderme mais amarela do que aqueles armazenados com 0,25 ou 20<FONT FACE=Symbol>m<img src="http:/img/fbpe/cr/v31n6/a05img01.gif" BORDER=0></FONT>.L-1 de etileno na atmosfera da câmara. A maçã 'Fuji' apresentou baixa sensibilidade a altas concentrações de etileno durante o armazenamento em AC, não se justificando a sua absorção em câmaras comerciais.<br>The experiment was carried out aiming to evaluate the effect of ethylene concentrations on the quality and occurrence of physiological disorders on Fuji apples stored in controlled atmosphere (CA) with 1kPa O2 / 0,2kPa CO2 at 0.5ºC. The treatments applied were: 0.25; 20; and 800<FONT FACE=Symbol>m<img src="http:/img/fbpe/cr/v31n6/Image8.gif" BORDER=0></FONT>.L-1 ethylene. The evaluations were accomplished after nine months of storage, at the opening of the chambers and after seven days in shelf life (25ºC). Only the fruits kept at 800<FONT FACE=Symbol>m<img src="http:/img/fbpe/cr/v31n6/Image8.gif" BORDER=0></FONT>.L-1 ethylene during storage period were influenced by the ethylene, showing higher respiration and ethylene biosynthesis, lower firmness and more yellow background color of the peel than those stored with 0.25 or 20<FONT FACE=Symbol>m<img src="http:/img/fbpe/cr/v31n6/Image8.gif" BORDER=0></FONT>.L-1. Fuji apples presented low sensibility to high ethylene concentrations during storage in AC, therefore absorption is not recomended in commercial storage rooms

Armazenamento de maçã 'gala' em atmosfera controlada com remoção de etileno Storage of 'gala' apple in controlled atmosphere with removal of ethylene

O objetivo deste trabalho foi avaliar o efeito de diferentes níveis de etileno na câmara sobre a manutenção da qualidade da maçã cv. Gala, durante o armazenamento em AC. O delineamento experimental utilizado foi inteiramente casualizado com quatro repetições e a unidade experimental composta por 50 frutos. Os tratamentos utilizados foram: >10µl L-1 (sem absorção); < 0,4µl L-1 e < 0,04µl L-1, cujos níveis mais baixos foram obtidos por absorção química. Após oito meses de armazenamento, na abertura das câmaras e após sete dias a 20&ordm;C, verificou-se maior firmeza de polpa, maior acidez titulável e menor ocorrência de podridões e degenerescência senescente nos frutos armazenados com remoção do etileno. Quanto aos teores de sólidos solúveis totais, não houve diferença estatística entre os tratamentos, em ambas as avaliações. A coloração da epiderme apresentou-se mais verde nos frutos armazenados sob remoção de etileno, após sete dias de exposição dos frutos a 20&ordm;C. A incidência de polpa farinhenta foi menor nos tratamentos com eliminação do etileno, na abertura das câmaras.<br>The objective purpose of this work was to evaluate the effect of different ethylene levels on the quality of cv. Gala apples during CA storage. The experimental design was completely randomized with 4 replications of 50 fruits. The treatments were: >10µl L-1 (without absorption); < 0.4µl L-1 and < 0.04µl L-1. After 8 month storage, at the chambers opening and after 7 days shelf life at 20&ordm;C fruits with ethylene absorption had higher firmness and titratable acidity and lower rot and senescent breakdown incidence. There was no statistic difference between treatments for TSS. After 7 days shelf life ground color was greener on the fruits stored with ethylene absorption. Mealy fruits incidence was lower with ethylene absorption, at the chambers opening

Soil biota in a megadiverse country: Current knowledge and future research directions in South Africa

Soils are integral to agricultural productivity, biodiversity, and the maintenance of ecosystem services. However, soil ecosystem research depends on foundational biological knowledge that is often missing. In this review, we present a comprehensive, cross-taxa overview of the soil biota of South Africa. We discuss the literature and sampling methods used to assess soil biota, the available taxonomic expertise and main collections within South Africa, the availability of identification guides and online resources, and the status and distribution of described species. We include species lists for all South African soil biota and, for groups with sufficient distribution records, species richness maps. Despite South Africa being only 0.8% of the earth’s terrestrial area, it contains nearly 1.8% of the world’s described soil species (mean per taxon 3.64%, range 0.17–15%; n = 36 groups), with nematodes and earthworms showing a remarkable (6.4 and 7.7%) proportion of globally described diversity. Endemism is high for most groups, ranging from 33–92%. However, major knowledge gaps exist for most soil biota groups. While sampling has been relatively comprehensive in some areas for a few groups (particularly those with direct socioeconomic impacts), the Nama-Karoo, Northern Cape and Eastern Cape are poorly sampled. Natural soils in biodiversity hotspots, such as the Fynbos Biome, are also understudied. We argue that a more integrative approach to acquiring foundational knowledge in soil biodiversity is needed if applied soil research is to be effective in ensuring sustainable soil health. Considerable investment will be required to bring our understanding of the soil biodiversity in this megadiverse region to a level where the Millennium Development Goals can be reached