Retention of allergic potential of parthenium following composting
Parthenium hysterophorus is known to cause allergic contact dermatitis (1). Changing clinical patterns of the dermatitis are reported (2, 3). Recently, the role of type I (immediate) and type III (Arthus phenomenon) has been postulated (4, 5). This weed, a native of tropical America, is wide spread in grasslands, fruit tree orchards, and arable land in neutral and acid soils. This weed interferes with the growth of other plants (allelopathic potential) resulting from the release of phytotoxic substances such as ferulic, caffeic, vanillic, chlorogenic, p-hydroxybenzoic acids, parthenin, ambrosin, and coronopilin, which inhibit the germination and growth of several crop plants (6). Because it has no economic value, efforts have been made to use parthenium as a green leaf manure, as a biopesticide, as a compost for agricultural purposes, and as an additive with cattle manure in biogas production (7). Compost obtained from parthenium can be used for agricultural purposes and as manure. This is likely to get widely dispersed, get airborne, and aggravate parthenium dermatitis if the allergenicity is retained. Parthenium compost was obtained from the Department of Agronomy, Tamil Nadu Agricultural University, Coimbatore. Compost made by 2 methods, anaerobic and aerobic, was collected. The composting procedure was carried out for 90 days for each of themethods. Samples were obtained on D45 and D90. The 2 methods of composting are described below.
Patch testing to detect Dermatitis and Allergies to plants.
Background and Objectives: Partheniumhysterophorous weed often referred to as ‘scourge of India’ is a major cause of systemic as well as cutaneous allergies ( Phyto-Dermatitis) in India. Awareness of the allergic potential of this weed is high in India but knowledge of its various allergic manifestations and related weeds is poor. Patch testing may reveal underlying sensitivity to the weeds in populations which are closely associated with them. This study is done to evaluate the awareness and prevalence of allergy to Parthenium and associated plants. Methods: Five hundred and fifty consenting subjects among the populations closely associated with plants were interviewed of which 202 with past history and/or signs, symptoms suggestive of plant allergy were tested. Results: Chrysanthemum was well recognized (89.6 %) than Parthenium (34.7%).Five subjects had a positive result for all antigens. Parthenium(9) Xanthium(8) and chrysanthemum (14) were the distribution of positive reactions among subjects. Overall 8.4% subjects had positive testing for one or more antigen. The age of 46-60 had the highest positivity. Farm workers were at maximum risk of acquiring allergy (14.5%), followed by green grocers/fruit sellers (11.8%), florists (10%) and horticulturists, gardeners,others (8%).Rural subjects had a higher positivity (10.6%) compared to Urban (6.5%). Interpretation and Conclusion: Majority of Subjects who could recognize and identify Parthenium and Xanthium as plants causing allergy were unsure of the potential risk from Chrysanthemum, a common commercial flowering plant and was unknowingly considered least allergic. But patch testing proved otherwise
Application of resource allocation optimisation to provide profitable options for dairy production systems
A linear program (LP) model analysed resource use on a 100 ha dairy farm. A single optimum-profit combination was established for resources which were either optimised or constrained. It was found that, with a fixed herd of 320 milking cows, when production increased from 305 kg milksolids per cow (kg MS/cow) to 415 kg MS/cow, cash profit increased by 65%. This required additional supplements. If, however, feed demand and supply were optimised at 415 kg MS/cow, the LP reduced milking cow number rather than buy in feed to meet the increased feed demand from higher production per cow. At all production levels chosen between 305 and 415 kgMS/cow, it was most economic to dry off and cull cows early in dry summers to optimise feed demand vs. feed grown; use nitrogen (N) fertiliser to avoid a feed deficit only when response rates of better than 10 kgDM to 1 kg N could be expected; not use N for growing supplements to harvest. Pasture cover, within defined constraint levels, provided a buffer for feed demand and supply fluctuations. The study highlights the importance of assessing production, income and cost in an integrated framework to identify the point at which individual resources become limiting.