Crop volume

Half-lives of two pesticides were estimated using the assumption that the decay was a first-order process. Half-lives were 28 8.5 days and 12 3.4 days for thiophanate-methyl and methiocarb, respectively. Crop volume was not a significant determinant of exposure using a grid count method. This was probably due to a large variation in the results with this method. 

Crop volume estimates ranged from 6.72 to 17.1 (v/v%), with a median of 11.1 and a mean of 11.3 (v/v%). The differences between crop volume estimates at the moment of HV and LV applications ranged from 0 to 3.8 (v/v%), depending on the elapsed time between applications. 

A possible relationship between DFR and the application rate, as well as the crop volume estimate (CrV), was investigated using a multiple linear regression model (ADFR = a + b AR + c CrV). No significant contribution of crop volume to the variation of ADFR was observed (p = 0.19 and p = 0.87 for high-volume applications and all applications, respectively). 

Popendorf et al. (1975) suggested a relationship between respiratory exposure and organic foliar dust released from the foliage due to crop disturbance therefore, it was hypothesized that crop density may be associated with both dermal and respiratory exposure. However, in the present study, no such relationship could be observed. This may be due to the large variation in the method used to determine crop volumes. Improvement of the crop-volume/leaf-surface-area method may contribute to the clarification of whether crop density can be considered a determinant of re-entry exposure. 

In conclusion it can be stated that the basic assumptions of the re-entry model — a linear relationship between application rate and initial dislodge-able foliar residue and a first-order decay of the DFR — have been confirmed. The relationship between the transfer factor and re-entry time at various DFR levels should be explored further. Including information on foliage surface area or crop density may lead to a refinement of the model however, crop volume estimating methods should be improved before their influence on the exposure processes can be fully evaluated. 

Chilver, A., Walker, T. S., Khatana, V, Fano, H., Suherman, R., Rizk, A. (2005). On-Farm Profitability and Prospects for True Potato Seed (TPS). In M. K. Razdan, A. K. Mattoo (Eds.), Genetic Improvement of Solanaceous Crops Volume I Potato (pp. 39-63). Science Publishers, Inc., Enfield. 

Vedamuthu, P.G.B., Khader, Md.A. and Rajan, F.S. (1994) Improvement of seed spices. In Chadha, K.L. and Rethinam, P. (eds) Advances in Horticulture - Plantation and Spice Crops, Volume 9, Part 1. Malhotra Publishing House, New Delhi, pp. 345-374. 

For marketed crops in a fully commercialized system, profit maximization would rarely be precisely the same as crop-volume maximization. Where labor was scarce, cultivators would be more concerned about maximizing the crop return per unit of labor, whereas if land was scarce, the return per acre would be the focus. 

A chain with cross-slats transports material up the bottom of the enclosed feederhouse and then into the threshing area. A front drum guides the chain onto plant material. Most combines have a position adjustment for the front drum (upper position for corn, lower position for small grains/other crops). Because many combines used for soybean harvesting frequendy alternate with corn harvesting, the position of the front drum should be set in the lower position unless crop volume is unusually large. 

Timmins, W.H. and Matter, A.D. 1992. Aspects of sweetpotato processing in Sichuan Province, People s Repubhc of China. In Product development for root and tuber crops. Volume I— Asia (G. Scott, S. Wiersema, and P.I. Fergusun, eds), pp. 217—228. Proceedings of an International Workshop, held April 22-May 1 at Visayas State College of Agriculture, ViSCA, Baybay, Leyte, Phillipines. CIP, Lima, Peru. 

Leaf thinning seems to be very effective, especially when practiced just after viraison. The result of this operation depends greatly on climate, variety and canopy placement. A partial leaf thinning before berry setting lowers the future crop volume, due to flower-fall. But this delicate technique can lower fertility during the following vegetative cycle (Candolfi-Vasconcelos and Koblet, 1990). 

Vine inflorescences can suffer from rot attacks if the climatic conditions are favorable to B. cinerea development. Peduncular rot causes flowers to fall and consequently a sharp drop in future crop volume. During the entire herbaceons growth period, the grape is resistant to this parasite. 

All on-vine overripening methods increase the ratio of sugar to acid. Grapes accumulate sugar while breaking down malic and/or tartaric acid. In all cases, this natural drying process lowers crop volume due to water loss. 

Hourly crop volume is considerable (from 4 to 10 tonnes per hour) and the daily duration is often 12 hours. 

Noble rot can reduce crop volume by up to 50%. Low crop yields of 15-25 hl/ha affect grape quality. 

Matthaus, B. (2012). Oil Technology. Technological Innovations in Major World Oil Crops. Volume 2 Perspectives. S. K. Gupta. Springer Science + Business Media, New York. 2. Perspectives 23-92. 

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