This article analyzes the incentives and compensation problems faced by cellulosic ethanol producer and logging firms and the consequent impact on the organization of the wood based cellulosic ethanol industry in the US. The success of this relationship is central to setting up the biofuel industry in Michigan and in the US at large. The study utilizes the theoretical framework of institutional economics and uses case methodology to discuss potential problems arising from information asymmetry. Theoretical results indicate that the specification contract under the principal-agent framework is of limited utility due to’ metering’ problem when the principal contracts with multiple agents for the supply of feedstock. Alternative arrangements including joint ventures have the potential to provide close to first best solutions.

Lantana camara L. (Verbanaceae) is an invasive plant widely distributed in Zimbabwe and is toxic to livestock and humans. Greenhouse and laboratory experiments were done at the Crop Science Department, University of Zimbabwe to assess the allelopathic effects of L. camara on Bidens pilosa and pearl millet. First, L. camara biomass was evaluated for its impact on the emergence and growth of B. pilosa and pearl millet, after the addition of 0, 10, 30, 40 and 50 g per pot (18 cm diameter x 17 cm depth each), under glasshouse conditions and adequate moisture conditions. Second, L. camara leaf extracts at 0, 10, 20, 30, 40 and 50 % concentrations were screened for their effects on the germination of B. pilosa and pearl millet under laboratory conditions. Randomized complete block designs, with 6 treatments replicated 4 times were used in both experiments. Lantana camara leaf biomass significantly (p<0.05) reduced the emergence and growth of B. pilosa, when it was added to the soil under glasshouse conditions. In contrast, pearl millet emergence and growth was not affected by L. camara. However, L. camara leaf extracts reduced the germination percentage, radicle length and plumule length of pearl millet under laboratory conditions.

Weed control is a serious problem in smallholder conservation agriculture farming areas in Zimbabwe. Green Manure Cover Crops (GMCCs), which improve soil fertility and reduce weeds through allelopathy, are likely to reduce the cost of weed control in these areas. A laboratory study was conducted at the University of Zimbabwe to investigate the effect of extracts of eleven GMCCs on the germination percentage, radicle and plumule length of Bidens pilosa, Eleusine indica and Pennisatum glaucum (pearl millet). A green house experiment was also done to determine the allelopathic potential of these GMCC extracts applied as soil incorporated residues on the emergence and dry matter production of E. indica, B. pilosa and Acanthospermum hispidum. GMCC extracts significantly reduced germination, radicle and plumule length of Pennisatum glaucum (P < 0.05) except for Crotalaria grahamiana and Raphanus sativas which had no effect on germination of Pearl millet. The emergence and dry matter of B. pilosa, E. indica and A. hispidum were significantly reduced by these legumes (P < 0.05) with the exception of common vetch (Vicia sativa) which stimulated the emergence of A. hispidum. Most of the legumes that were used in this study have allelopathic effects on B. pilosa, E. indica and A. hispidum.

Belonging to one of begonia leaf plants is Begonia rex cultorum, this group belong to the class of rex begonians. An ornamental plant species are known for the leaf colour and pattern. The objective of research to study growth and quality of Begonia rex-cultorum ’Marmaduke’ caused by application of paclobutrazol and shading levels. This experiment was arranged in Split Plot Design consisted of two factors with shading as main plot and paclobutrazol concentration as subplot. The mainplot consisted of three levels, ie., light shading; moderate shading; and heavy shading. The second factor was concentrations of paclobutrazol application consisted of four levels, i.e., without paclobutrazol, 1 ppm paclobutrazol, 2 ppm paclobutrazol and 3 ppm paclobutrazol. The experiment consisted of 12 treatments units with three replications. The result of this experiment showed that there was significant interaction between levels of shading and paclobutrazol concentrations on average leaf area. Application of 3 ppm paclobutrazol with heavy shading gave the lowest average leaf area, whereas non paclobutrazol treatment with heavy shading gave highest average leaf area on 12 weeks after treatment. Treatment of light shading decreased specific leaf area compared with heavy shading. However treatment of 3 ppm paclobutrazol decreased plant height, plant canopy diameter, petiole length, petiole diameter, and specific leaf area, but it increased number of bud tips and number of leaves compared without application of paclobutrazol. Treatment of paclobutrazol (1 ppm, 2 ppm and 3 ppm) on all of shading levels (light, moderate, and heavy) gave higher consumers preference of shoot structure and leaf color compared with non treatment of paclobutrazol on all of shading levels.

The number of rice mills in Uganda increased rapidly during the past decade, in response to increasing demand for milling services. However, despite the notable improvement in access to milling services, recent studies have shown that some farmers still sell rice in unmilled form which attracts lower prices. This study was undertaken to examine why some rice farmers still sell un-milled rice in the advent of improved access to milling services. Descriptive statistical methods of data analysis were used to characterize rice-growing households by the form in which they sell rice, before fitting a Tobit model to determine the factors influencing the proportion of rice sold as grain after milling. The returns (gross margins) to rice-milling were also estimated. The study findings show that rice production is profitable regardless of the form in which it is sold; and the majority of households invest in milling all or part of their rice before sale. However, although milling households incurred higher costs, they also had higher gross margins, implying that selling milled rice is more profitable than selling paddy. The price of milled rice, volume of harvested rice, household size and group membership have significant and positive relationships with the proportion of rice sold as grain; while distance to the nearest rice mill is negatively and significantly associated with the proportion of rice sold as grain.

The protracted change in climatic conditions because of the natural or anthropogenic activities is termed as climate change. It is mainly caused by human induced emission of greenhouse gases like Carbon dioxide CO2, Methane CH4, Nitrous oxide NO2. These gases trap the sunlight, rising the earth’s temperature and altering the pattern of precipitation, humidity across countries and causing some sever damages to the economies. Yearly data (from 1971 to 2009) published by the Metrological Department of Pakistan and Agriculture Statistics of Pakistan is being used. Vector Autoregressive Modeling is applied to study the impact of the climate change on wheat productivity. The result of the model shows that the rising temperature leads to reduction in output as the variation in the wheat productivity has been brought mainly by the variation in the temperature that is 25 percent in the tenth period as shown by the variance decomposition.

This study aims at determining the manufacturing process of tea from Lippia multiflora collected in Côte d’Ivoire and describe its various uses. A survey was conducted among pickers, sellers and consumers in five cities (Abidjan, Yamoussoukro, Toumodi, Katiola and Bondoukou). The results show that (92.11%) of the women harvesting tea, cut leafy stems at tea tree base, (80.65%) carry their harvests on the head and (60.95%) dry their harvest from 1 to 3 days or 7 days. The harvest period ranging from April to August is the most important one (80.15%). In Abidjan, the use of Lippia multiflora as food is 79.80 % and in other areas of the country, it is used for both food and medicine with the respective frequencies of 46.56 and 46.44 % and its insecticidal use represents only (6,16%). It appears from this survey that the leaves of Lippia multiflora are most used by consumers; the manufacturing of this herbal tea is performed according to traditional process. The savannah tea has nutritional, insecticidal and medicinal values. It would be better to afford the opportunity to transform the leaves of Lippia multiflora in tea in order to have a crop with a high added value.

The dust accumulation capacity of fruiting plants was evaluated from eight different sites in and around Multan. The impact of dust accumulation/deposition was observed via various foliage (leaf area, fresh and dry weights, stomatal clogging) and biochemical attributes (chlorophyll contents, carotenoids & ascorbic acid) from leaves of these species. The maximum dust accumulation/deposition was occurred in the plants growing at Road sides while, the minimum dust was found on plants growing at Bahauddin Zakariya University. Dust accumulation has caused a significant effect on almost all foliage and biochemical attributes of all the plant species. Foliage attributes of all the plant species showed species specific responses because in some plants a positive correlation was observed between foliage attributes and dust load but in other plants it is negative. Biochemical responses had shown an inconsistency as chlorophylls (b & total) contents decreased and ascorbic acid contents increased with an increase in dust accumulation/deposition in all the plant species, except chlorophyll a and carotenoid contents which give species specific response to dust pollution. A negative correlation was found between dust deposition and chlorophyll b and total contents. Whereas, accumulation of ascorbic acid was associated with a decline in pigment contents.

Changes in morphological structure of rice varieties and shifting paradigm of cultivation have brought forth marked change in floristic composition of weed flora, weed density and their virulence. These have compounded weed problem further. Yield losses caused by weed species in rice are enormous. With increasing weed density, yield losses are increasing markedly. Several weed management methods viz., cultural, manual, mechanical and chemical methods used for controlling weeds under lowland rice ecosystem were discussed in this review. Each control method has advantages and disadvantages. Weeds have a variable growth habit and life cycles so that no single method can effectively control weeds in all situations. Thus, integrated weed management approach is the urgent requirement for sustainable rice production.