The Horseshoe Crab Conundrum; can we Harvest and Conserve?

Dr. Jennifer Mattei and Dr. Mark Beekey lead efforts to monitor and conserve horseshoe crabs by means of Project Limulus. The effort enlists volunteers to help document the movements and mating practices of horseshoe crabs.

Influence of Crop Load on Tree Growth, Yield, and Fruit Quality of Scab Resistant Apples at Harvest

Apple scab, caused by Venturia inaequalis, is a major disease affecting apple production. Breeding programs have developed over 30 releases of scab-resistant cultivars since 1970 with recent ones having much improved quality. Redfree and GoldRush are from a cooperative breeding program involving Purdue, Rutgers, and Illinois universities while Liberty was introduced from the Cornell University breeding program. For these cultivars to gain better acceptance, more information is needed on their cropping capacities and the effect of crop load on fruit quality attributes. Our study was conducted to determine the relationship between increasing crop load on tree growth, fruit size, and fruit quality variables of the three cultivars under Iowa conditions.

Selection and utilization of the early harvest list : evidence from the Free Trade Agreement between China and Taiwan

In this paper, we conducted an empirical investigation into the determinants of FTA utilization in exports from Taiwan to China. To do this, we first estimated the selection equation to see what kinds of products are included in the early harvest list. As a result, we found that Taiwan includes products with a medium magnitude of benefits from tariff removal in the early harvest list. Taiwan also includes products for which ASEAN countries have better access to the China market. We then estimated the equation for the determinants of FTA utilization by introducing an inverse of the Mills ratio estimated in the selection equation. The findings are that, as usual, the FTA rates are more likely to be utilized for products with a larger tariff margin. In addition, some rules of origin are found to be relatively restrictive in terms of discouraging trade.

Local burning velocity in a Bunsen jet flame

A PIV-based system has been set-up for the simultaneous measurement of the local burning velocity of premixed flames and the flame stretch due to the flame front curvature and the incoming flow strain rate. For moderately short jet flames, these measurements allow an indirect determination of the Markstein length, according to Clavin and Joulin (C–J) theory. For tall flames, the flame curvature becomes relatively large in a region around the tip where the C–J theory breaks down. However, our experiments confirm the appearance of a new linear relation between burning velocity and curvature at the flame tip. This relation defines a new proportionality factor which is probably associated to the evolution from rounded tips to slender tips when the jet velocity is increased.

Fruit quality sensing:Post-harvest ripeness

Firmness sensing of selected varieties of apples, pears and avocado fruits has been developed using a nondestructive impact technique. In addition to firmness measurements, postharvest ripeness of apples and pears was monitored by spectrophotometric reflectance measurements, and that of avocadoes by Hunter colour measurements. The data obtained from firmness sensing were analyzed by three analytical procedures: principal component, correlation and regression, and stepwise discriminant analysis. A new software was developed to control the impact test, analyse the data, and sort the fruit into specified classes, based on the criteria obtained from a training procedure. Similar procedures were used to analyse the reflectance and colour data. Both sensing systems were able to classify fruits w i th good accuracy.

Mechanical segregation of apricot varieties and their ripeness levels at harvest

Some laboratory tests consisting on quasi-static compression and puncture forces carried out on twelve varieties of apricot during 1990 and 1991 were effective in sorting them. These mechanical properties show a high correlation w i th the ethylene production rate per fruit, so allowing to discriminate between ripeness levels at harvest. In this study it is also demonstrated that puncture seems to be the less variable mechanical test. The values (N/mm) obtained with it show a highly significant correlation with compression resistance and with quasi-static compression damage of the fruits.

Actual state of the mechanization of harvest of fruits and vegetables in Spain.

A review of the actual methods of harvest of fruits and vegetables in Spain is made. Special emphasis is given to the main horticultural Spanish crops that can be harvested by machines like green, beans, green peas broad beans, tomatoes, lettuces and chufas, as vegetables, and olives almonds, cherries, apples pears apricots, etc. as fruits.

Industry-peppers harvest mechanization.

Production of peppers for deshidration (paprika) and for extraction of natural colorants is of great importance in some Mediterranean irrigation areas. In the area of Badajoz (Spain) traditional production, handling and postharvest systems are no longer feasible, although a very good quality and potential market exist for this product. All aspects of mechanized production and handling have been addressed: direct seeding and transplanting, cultivation systems and mechanical harvesting are searched to be adopted in a new production system. A study of size, shape and fruiting pattern of the new varieties was performed. A feasibility study of mechanized harvesting was also made. Results of field testing of different types of harvesters and performance of existing picking heads are presented, some of which yield a feasible solution for the growers of industry peppers in the area. The design, construction and field testing results of a new picking head based on the double-helix principle is presented.