Effects of different management methods for sunn-hemp cover crop on corn production in a no-till system in Cambodia

Authors: HIN, LYHOUR - Royal University Of Agriculture; Kornecki, Ted; REYES, MANUEL - Kansas State University; TIVET, FLORENT - University Of Montpellier; HOK, LYDA - Royal University Of Agriculture; BUNTONG, BORARIN - Royal University Of Agriculture; LOR, LYTOUR - Royal University Of Agriculture; LENG, VIRA - Ministry Of Agriculture Forestry And Fisheries; SUOS, VUTHY - Ministry Of Agriculture Forestry And Fisheries; CLEMMONS, HORACE - Cleber/oggun

Submitted to: Applied Engineering in Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/30/2021
Publication Date: 10/19/2021
Citation: Hin, L., Kornecki, T.S., Reyes, M., Tivet, F., Hok, L., Buntong, B., Lor, L., Leng, V., Suos, V., Clemmons, H. 2021. Effects of different management methods for sunn-hemp cover crop on corn production in a no-till system in Cambodia. Applied Engineering in Agriculture. 37(5):805-818. https://doi.org/10.13031/aea.14345.
DOI: https://doi.org/10.13031/aea.14345

Interpretive Summary: ARS scientist located in Auburn, AL conducted a field experiment testing no-till equipment he developed under Cambodia’s soil and climatic conditions. The study compares the efficiency of two seeder types in sowing corn on three sunn hemp cover crop residue retention methods utilizing experimental rollers/crimpers. Residue incorporation by disking in used as a control for comparison. Corn population, stalk diameter, ear length, and ear diameter was not affected by residue retention methods alone but were affected by the combination of seeder type and residue retention treatments. The corn yield was not influenced by residue retention methods or planter type. Soil volumetric moisture content experienced higher soil moisture for rolled/crimped residue retained compared with the residue incorporated by disking. This study indicates the use of no-till systems with cover crops is feasible in Cambodia but identified problems with wrapping of sunn hemp residue on planters which must be resolved for efficient cash crop planting. However, future research must include multi- year field experiments focused on improving no-till equipment to optimize its performance in Cambodia’s soil and climatic conditions. In addition to equipment development, future studies must concentrate on agronomic aspects leading to increased yields and improved soil health for sustainable no-till production systems.

Technical Abstract: Conservation agriculture (CA) is gaining popularity in Cambodia to sustain soil fertility, productivity, and profits. However, the adoption remains slow due to low engagement of local services into CA machinery and technology. Therefore, this paper aimed to compare different no-till seeders and residue retention methods for corn (Zea mays L.) sowing and to determine their effects on growth and yield. The experiment was conducted in Rattanak Mondul District, Battambang Province, in the wet season of 2019. Sunn hemp (Crotalaria juncea L.) was grown as a cover crop for 74 days prior to corn. Each main plot was 14 m x 34 m and was subdivided lengthwise with 4.0-m buffers for operations of two different seeders, namely one-row Morrison seeder mounted on 14 kW Oggun tractor and four-row Brazilian seeder mounted on 56 kW John Deere tractor. The results show that using Brazilian seeder saved around 50% of seed and 80% of time, when compared with Morrison seeder. Plant population, plant diameter, and kernel characteristics were also significantly greater with Brazilian seeder, when compared to the Morrison seeder. Plots treated with the Brazilian seeder and Cambodia made crimper had larger ear size and weight. Volumetric Moisture Content (VMC) was significantly affected by residue retention with higher VMC for rolled and crimped residue compared to disked/incorporated residue. The study demonstrates that using no-till equipment such as roller/crimpers and no-till planters is feasible in Cambodia’s small farming systems; although more research is needed to study long-term effects on crop yields and soil health.