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Olpidiopsis is a genus of obligate holocarpic endobiotic oomycetes. Most of the species classified in the genus are known only from their morphology and life cycle, and a few have been examined for their ultrastructure or molecular phylogeny. However, the taxonomic placement of all sequenced species is provisional, as no sequence data are available for the type species, O. saprolegniae, to consolidate the taxonomy of species currently placed in the genus. Thus, efforts were undertaken to isolate O. saprolegniae from its type host, Saprolegnia parasitica and to infer its phylogenetic placement based on 18S rDNA sequences. As most species of Olpidiopsis for which sequence data are available are from rhodophyte hosts, we have also isolated the type species of the rhodophyte-parasitic genus Pontisma, P. lagenidioides and obtained partial 18S rDNA sequences. Phylogenetic reconstructions in the current study revealed that O. saprolegniae from Saprolegnia parasitica forms a monophyletic group with a morphologically similar isolate from S. ferax, and a morphologically and phylogenetically more divergent species from S. terrestris. However, they were widely separated from a monophyletic, yet unsupported clade containing P. lagenidioides and red algal parasites previously classified in Olpidiopsis. Consequently, all holocarpic parasites in red algae should be considered to be members of the genus Pontisma as previously suggested by some researchers. In addition, a new species of Olpidiopsis, O. parthenogenetica is introduced to accommodate the pathogen of S. terrestris.

A field survey was conducted to compare the working performance and cost of three types of power tillers for tillage operations in the Kampar Region of Riau Province in Indonesia. A total of 22 rotary tillers, 11 moldboard plows, and 27 hydro tillers were purposively selected from seven districts in the region. The managers, custom operators, and mechanics of these machines were interviewed in 2012 and 2013 to collect data. The results showed that hydro tillers were the best in terms of their working performance, operational cost savings, and profitability. These machines must be employed for only 3.07ha/season for operators to break even. For these reasons, it is suggested that farmers would benefit most by choosing hydro tillers for tillage operations.

This research examines the availability of mechanical power and estimates the labor requirements and costs for small-scale rice farming operations in Riau Province, Indonesia. In 2010, we interviewed 120 farmers from the Siak and Kampar Regencies to collect data. We found that farming operations are predominantly performed by human labor because of the lack of farm machines. Between 2001 and 2010, the average availability of mechanical power was just 0.31 hp/ha and this only increased by 0.75% annually. Therefore, annual rice farming operations required 83.26 man-days/ha compared with 7 machine-days/ha. The total cost per hectare for these operations was IDR 7,895,830 (US $877), contributed mostly by labor costs. Farmers should thus adopt more machines to save labor, time, and cost

Successful operation of a farming system is determined greatly by availability of farm power. The objective of this research was to examine the farm power status and requirement for small-scale rice farming operations in Riau Province. Primary and secondary data were gathered from various sources. A total of 120 farmers were interviewed to collect data primer from two selected rice centres in two regencies of the province during the 2008 rainy cropping season. The main source of farm power practiced by small rice farmers is human labour and mechanical power. The total power available is still very low and remains under the minimum requirement for an efficient agriculture. The stage of the rice mechanization process is also relatively low and still below the take-off stage of the critical point of the mechanization process. Under these conditions, the availability of farm power has no effect on total cultivated area and yield of rice over years. The total energy required per hectare of rice farm operations was 418 kW-h (561 hp) on average. Although mechanized farm operations need more power, the total operation hours would decrease significantly. The efforts should be taken to continuously encourage small farmers to adopt mechanical power in order to carry out timely farm operations and make the rice production process more productive and efficient.

This paper presents the capability of tractor operators in performing repair and maintenance of small tractors, the availability of service and repair facilities at the farm level, and the manner of the operators in maintaining their tractors. Data are based on field visits and interviews with 65 tractor operators from 6 villages collected in three regencies of Riau Province. The results show that most operators lack the technical skill to service and repair tractors due to insufficient training, specific education, and work experience. Inadequate repair and maintenance facilities, such as workshops, mechanics, and spare part depots cause delays in repair work and raise the price of spare parts in the survey areas. Farmers do not keep accurate service records and most of them disregard proper maintenance and service of their tractors, such as changing engine oil without following the manufacturer’s recommendations. Provincial governments should provide training facilities and a program to improve the technical knowledge and skills of the operators and local mechanics. Repair and maintenance facilities should be established in village areas to guarantee timely repair in case of breakdowns and to make spare parts available at low price. The operators should keep service records accurately and adhere to maintenance and service schedules according to the manufacturer’s instructions. They should also be encouraged to properly service and maintain their tractors.