Microbial use of organic substrates and maize growth, especially in saline and alkaline soils of Pakistani Punjab

This thesis consists of 4 main parts: (1) impact of growing maize on the decomposition of incorporated fresh alfalfa residues, (2) relationships between soil biological and other soil properties in saline and alkaline arable soils from the Pakistani Punjab, (3) decomposition of compost and plant residues in Pakistani soils along a gradient in salinity, and (4) interactions of compost and triple superphosphate on the growth of maize in a saline Pakistani soil. These 4 chapters are framed by a General Introduction and a Conclusions section. (1) In the first study, the effects of growing maize plants on the microbial decomposition of freshly chopped alfalfa residues was investigated in a 90-day pot experiment using a sandy arable soil. Assuming that the addition of alfalfa residues did not affect the decomposition of native soil organic matter, only 27% of the alfalfa residues were found as CO2. This suggests that a considerable part of alfalfa-C remained undecomposed in the soil. However, only 6% of the alfalfa residues could be recovered as plant remains in treatment with solely alfalfa residues. Based on d13C values, it was calculated that plant remains in treatment maize + alfalfa residues contained 14.7% alfalfa residues and 85.3% maize root remains. This means 60% more alfalfa-C was recovered in this treatment. (2) In the second study, the interactions between soil physical, soil chemical and soil biological properties were analysed in 30 Pakistani soils from alkaline and saline arable sites differing strongly in salinisation and in soil pH. The soil biological properties were differentiated into indices for microbial activity, microbial biomass, and community structure with the aim of assessing their potential as soil fertility indices. (3) In the third study, 3 organic amendments (compost, maize straw and pea straw) were added to 5 Pakistani soils from a gradient in salinity. Although salinity has depressive effects on microbial biomass C, biomass N, biomass P, and ergosterol, the clear gradient according to the soil salt concentration was not reflected by the soil microbial properties. The addition of the 3 organic amendments always increased the contents of the microbial indices analysed. The amendment-induced increase was especially strong for microbial biomass P and reflected the total P content of the added substrates. (4) The fourth study was greenhouse pot experiment with different combinations of compost and triple superphosphate amendments to investigate the interactions between plant growth, microbial biomass formation and compost decomposition in a strongly saline Pakistani arable soil in comparison to a non-saline German arable soil. The Pakistani soil had a 2 times lower content of ergosterol, a 4 times lower contents of microbial biomass C, biomass N and biomass P, but nearly a 20 times lower content of NaHCO3 extractable P. The addition of 1% compost always had positive effects on the microbial properties and also on the content of NaHCO3 extractable P. The addition of superphosphate induced a strong and similar absolute increase in microbial biomass P in both soils.

Identifying the component structure of job satisfaction by principal components analysis among extension officers in North West Province, South Africa

The component structure of a 34-item scale measuring different aspects of job satisfaction was investigated among extension officers in North West Province, South Africa. A simple random sampling technique was used to select 40 extension officers from which data were collected. A structured questionnaire consisting of 34 job satisfaction and 10 personal characteristic items was administered to the extension officers. Items on job satisfaction were measured at interval level and analyzedwith Principal ComponentAnalysis. Most of the respondents (82.5%) weremales, between 40 to 45 years, 85% were married and 87.5% had a diploma as their educational qualification. Furthermore, 54% of the households size between 4 to 6 persons, whereas 75% were Christians. The majority of the extension officers lived in their job area (82.5), while 80% covered at least 3 communities and 3 farmer groups. In terms of number of farmers covered, only 40% of the extension officers covered more than 500 farmers and 45% travelled more than 40 km to reach their farmers. From the job satisfaction items 9 components were extracted to show areas for job satisfaction among extension officers. These were in-service training, research policies, communicating recommended practices, financial support for self and family, quality of technical help, opportunity to advance education, management and control of operations, rewarding system and sanctions. The results have several implications for motivating extension officers for high job performance especially with large number of clients and small number of extension agents.

Soil fertility and nutrient status of traditional Gayo coffee agroforestry systems in the Takengon region, Aceh Province, Indonesia

Little is known about the traditional coffee cultivation systems in Central Aceh, Indonesia, where coffee production is a major source of income for local Gayo people. Based on field observations and farmer interviews, 14 representative agroforestry coffee plantations of different age classes (60-70 years, 30-40 years, and 20 years) as well as seven adjacent grassland and native forest sites were selected for this study, and soil and coffee leaf samples collected for nutrient analysis. Significant differences in soil and coffee leaf parameters were found between former native forest and Sumatran pine (Pinus merkusii) forest as previous land cover indicating the importance of the land use history for today’s coffee cultivation. Soil pH as well as exchangeable Na and Ca concentrations were significantly lower on coffee plantations compared to grassland and forest sites. Soil C, N, plant available P, exchangeable K, and Mg concentrations showed no consistent differences between land use groups. Nitrogen (N), phosphorus (P), and potassium (K) concentrations of coffee leaves were in the sufficiency range, whereas zinc (Zn) contents were found to be consistently below the sufficiency threshold and significantly lower in coffee plantations of previous pine forest cover compared to those of previous native forest cover. While the results of this study provided insights into the nutrient status of coffee plantations in Central Aceh, the heterogeneity of site conditions, limited sampling size, and scarcity of reliable data about the land use history and initial soil conditions of sampled sites preclude more definitive conclusions about the sustainability of the studied systems.

Swamp buffalo keeping – an out-dated farming activity? A case study in smallholder farming systems in Xishuangbanna, Yunnan Province, PR China

Expansion of rubber tree plantations and agricultural mechanization caused a decline of swamp buffalo numbers in the Naban River National Nature Reserve (NRNNR), Yunnan Province, China. We analysed current use of buffaloes for field work and the recent development of the regional buffalo population, based on interviews with 184 farmers in 2007/2008 and discussions with 62 buffalo keepers in 2009. Three types of NRNNR farms were distinguished, differing mainly in altitude, area under rubber, and involvement in livestock husbandry. While pig based farms (PB; n=37) have abandoned buffalo keeping, 11% of the rubber based farms (RB; n=71) and 100% of the livestock-corn based farms (LB; n=76) kept buffaloes in 2008. Herd size was 2.5 +/-1.80 (n=84) buffaloes in early 2008 and 2.2 +/-1.69 (n=62) in 2009. Field work on own land was the main reason for keeping buffaloes (87.3 %), but lending work buffaloes to neighbours (79.0%) was also important. Other purposes were transport of goods (16.1%), buffalo trade (11.3%) and meat consumption (6.4%). Buffalo care required 6.2 +/-3.00 working hours daily, while annual working time of a buffalo was 294 +/-216.6 hours. The area ploughed with buffaloes remained constant during the past 10 years despite an expansion of land cropped per farm. Although further replacement of buffaloes by tractors occurs rapidly, buffaloes still provide cheap work force and buffer risks on poor NRNNR farms. Appropriate advice is needed for improved breeding management to increase the efficiency of buffalo husbandry and provide better opportunities for buffalo meat sale in the region.

Farmers’ desired traits and selection criteria for maize varieties and their implications for maize breeding: A case study from KwaZulu-Natal Province, South Africa

Adoption of hybrids and improved varieties has remained low in the smallholder farming sector of South Africa, despite maize being the staple food crop for the majority of households. The objective of this study was to establish preferred maize characteristics by farmers which can be used as selection criteria by maize breeders in crop improvement. Data were collected from three villages of a selected smallholder farming area in South Africa using a survey covering 300 households and participatory rural appraisal methodology. Results indicated a limited selection of maize varieties grown by farmers in the area compared to other communities in Africa. More than 97% of the farmers grew a local landrace called Natal-8-row or IsiZulu. Hybrids and improved open pollinated varieties were planted by less than 40% of the farmers. The Natal-8-row landrace had characteristics similar to landraces from eastern and southern Africa and closely resembled Hickory King, a landrace still popular in Southern Africa. The local landrace was preferred for its taste, recycled seed, tolerance to abiotic stresses and yield stability. Preferred characteristics of maize varieties were high yield and prolificacy, disease resistance, early maturity, white grain colour, and drying and shelling qualities. Farmers were willing to grow hybrids if the cost of seed and other inputs were affordable and their preferences were considered. Our results show that breeding opportunities exist for improving the farmers’ local varieties and maize breeders can take advantage of these preferred traits and incorporate them into existing high yielding varieties.

Smallholder farmers’ access to credit in the Amathole District Municipality, Eastern Cape Province, South Africa

Provision of credit has being identified as an important instrument for improving the welfare of smallholder farmers directly and for enhancing productive capacity through financing investment by the farmers in their human and physical capital. This study investigated the individual and household characteristics that influence credit market access in Amathole District Municipality, Eastern Cape Province, South Africa, using a cross sectional data from smallholder farmers’ household survey. The aim is to provide a better understanding of the households’ level socio-economic characteristics, not only because they influence household’s demand for credit but also due to the fact that potential lenders are most likely to base their assessment of borrowers’ creditworthiness on such characteristics. The results of the logistic regression suggest that credit market access was significantly influenced by variables such as gender, education, households’ income, value of assets, savings, dependency ratio, repayment capacity and social capital. Implications for rural credit delivery are discussed.

Factors affecting choice of financial services among rural consumers: Emerging experiences from Gicumbi District, northern Province in Rwanda

Enhancement of financial inclusivity of rural communities is often recognised as a key strategy for achieving economic development in third world countries. The main objective of this study was to examine the factors that influence consumers’ choice of a rural bank in Gicumbi district of Rwanda. Data was collected using structured questionnaires and analysed using a binary probit regression model and non-parametric procedures. Most consumers were aware of Popular Bank of Rwanda (BPR) and Umurenge SACCO through radio advertisements, social networks and community meetings. Accessibility, interest rates and quality of services influenced choice of a given financial intermediary. Moreover, the decision to open a rural bank account was significantly influenced by education and farm size (p<0.1). These results indicate the need for financial managers to consider these findings for successful marketing campaigns.