New mexico pod–type green chile ( Capsicum annuum ) is one of New Mexico’s leading horticultural commodities. Cultivated acreage of green chile in New Mexico is threatened because of the high cost and insufficiently available labor for hand harvest. Therefore, mechanization is necessary to sustain the industry. Successful mechanization depends on harvester design coupled with plant architecture that optimizes harvest yield and quality. Harvested green fruit must be whole, unbroken, and unblemished for fresh and processed markets, so harvester design and plant architecture must maximize yield while minimizing fruit damage. In two trials conducted at the New Mexico State University Agricultural Science Center in Los Lunas, six cultivars (AZ-1904, Machete, PHB-205, E9, PDJ.7, and RK3-35) were evaluated for plant architecture and harvest efficiency with a double, open-helix mechanical harvester with two counter-rotating heads. Cultivars were direct seeded on 17 Apr. 2015 and 14 Apr. 2016 and managed according to standard production practices. Plant architecture traits, plant width, plant height, height to first primary branch, distance between first primary branch and first node, basal stem diameter, and number of basal branches were measured before harvest. Mechanical harvest yield components, which included marketable fruit, broken fruit, ground fall losses, unharvested fruit remaining on branches, and nonpod plant material, were assessed after once-over destructive harvests on 2 Sept. 2015 and 31 Aug. 2016. Fruit width, fruit length, and pericarp thickness were measured from a representative sample of 10 marketable fruit. In 2015, ‘AZ-1904’ and ‘PDJ.7’ had significantly ( P ≤ 0.05) more marketable yield than ‘Machete’ that had the least marketable yield. No statistically significant differences were found in marketable yield in 2016. When both years were combined, ‘PDJ.7’ had significantly more nonpod plant material harvested and the plants were taller than all other cultivars. We found mechanical harvest performance to be significantly affected by plant height, with shorter plants yielding less marketable fruit. Despite differences in fruit wall thickness, no significant differences were measured in broken fruit. In 2015, ‘AZ-1904’ had significantly less basal branches per plant, reducing obstruction for the picking mechanism. Harvest efficiencies (marketable harvested fruit yield as a percentage of total plot yields) ranged from 64.6% to 39.3% during this 2-year trial, with the highest harvesting cultivars PDJ.7 and AZ-1904. In the future, all new mexico pod–type green chile breeding efforts for mechanical harvest must incorporate desirable plant architecture traits to increase harvest efficiencies.

Paprika-type chile (Capsicum annuum L.) crops are susceptible to plant population losses through pest activity, disease, and extreme weather events such as hail storms. This study was conducted to determine the influence of intensity and timing of plant population reductions on the final harvested yield of paprika-type chile so that informed decisions can be made regarding continuing or ending a damaged field. Two trials, one per year, were conducted in southern New Mexico. ‘LB-25’, a standard commercial cultivar, was direct seeded on 29 March 2016 and 4 April 2017. Plants were thinned at three different growth stages; early seedling, first bloom, and peak bloom. Plants were thinned to four levels at each phenological stage; 0% stand reduction (control; ~200,000 plants/ha), 60% stand reduction (~82,000 plants/ha), 70% stand reduction (~60,000 plants/ha), and 80% stand reduction (~41,000 plant/ha). In both years, the main effects of stand reduction had a significant impact on harvested yield, emphasizing the percentage of stand reduction has more of an impact on yield than timing in paprika-type red chile. Consistently, an 80% stand reduction in paprika-type chile significantly reduced fresh red chile yield by 26% to 38%.

Lettuce ( Lactuca sativa ) is a high-value crop cultivated worldwide. Harvested lettuce acreage in New Mexico, USA, trails the leading lettuce production states (California, Arizona), but growers in New Mexico are interested in expanding their production. For New Mexico farmers to increase lettuce production to reach new markets, information on heat-tolerant cultivar performance is needed. This study was conducted to evaluate six lettuce cultivars described as heat tolerant by seed suppliers or other sources. In 2020 and 2021, we assessed two butterhead types, ‘Anuenue’ and ‘Mikola RG10’; two green leaf types, ‘Muir’ and ‘Tropicana’; and two romaine types, ‘Parris Island Cos’ and ‘Sparx’, in the Jose Fernandez Garden at the New Mexico State University Heritage Farm in Las Cruces, NM. To determine which cultivars and types of lettuce are better suited for southern New Mexico, we measured these variables: marketable harvest weight, number of days from transplant to first bolt, and number of days from transplant to 50% bolted. In 2020, ‘Sparx’, a romaine-type lettuce, had, on average, 32% higher yield compared with the other lettuce types. In 2021 both romaine-type cultivars, Sparx and Parris Island Cos, produced 19% more marketable yield than the other lettuce cultivars. In 2020, ‘Sparx’ was the last to bolt and to reach the 50% bolted stage, whereas in 2021 ‘Mikola RG10’ and ‘Muir’ were the last cultivars to bolt and reach the 50% bolted stage. These results suggest that ‘Sparx’ would be a good potential candidate for farmers in southern New Mexico. ‘Mikola RG10’ and ‘Muir’, butterhead and green leaf type, respectively, demonstrated slower bolting in 2021, indicating they may be useful cultivars for extending lettuce harvest in New Mexico.

Curtovirus spp., a group of widely distributed geminiviruses, are among the most significant plant pathogens in the United States. Beet curly top virus (BCTV), vectored by the beet leafhopper [ Circulifer ( Neoaliturus ) tenellus Baker], causes severe economic losses in crops such as tomatoes, peppers, dry beans, sugar beets, melons, and leafy greens, particularly in the western United States. In New Mexico, chile ( Capsicum annuum ) is vulnerable, with infected plants exhibiting symptoms such as stunting, chlorotic and curled leaves, misshapen fruits, reduced yields, and plant death. Yield losses can reach up to 50% in some years. Current management strategies, including pesticide applications, provide limited protection, leaving growers with substantial losses. Research indicates beet leafhoppers prefer full sun and avoid shaded areas, suggesting potential for innovative pest management strategies. Agrivoltaic systems (AVSs), which combine photovoltaic (PV) installations with agriculture, increase field shade and could potentially deter crop pests. However, the effect of AVS on pest management and chile crop yields remains underexplored. This study evaluated the impact of AVS shade on chile yield and plant growth, beet leafhopper abundance, and BCTV incidence. In 2023 and 2024, ‘NuMex Odyssey’, a New Mexico type chile cultivar, was grown in PV module–shaded and full sun replications at New Mexico State University’s Leyendecker Plant Science Research Center. PV modules provided shade to plants during the morning hours (0630 to 1330 HR), resulting in an 11% reduction in mean light intensity compared with the full sun replications. Full sun replications had more marketable green yield, while PV shaded replications exhibited significantly lower BCTV-affected fruit in 2024 and beet leafhopper abundance in both 2023 and 2024. These findings suggest that shading can reduce beet leafhopper abundance and BCTV incidence, offering potential benefits for chile cultivation.

New Mexico green pod-type chile ( Capsicum annuum ) has significant importance as a vegetable crop. The cultivation and trade of New Mexico pod-type green chile are culturally significant within New Mexico (USA) and contribute to the state’s economy by providing income and employment to farmers and through supporting industries. However, because of the high cost and limited availability of labor, New Mexico pod-type green chile acreage has declined. Traditionally, New Mexico pod-type green chile is hand-harvested when the fruit are full-size but physiologically immature. To preserve and expand the production of New Mexico pod-type green chile, the adoption of mechanical harvest technologies is essential. In 2015 and 2016, experiments were conducted at New Mexico State University’s Los Lunas Agricultural Science Center (Los Lunas, NM, USA) to examine the effects of increased planting density on New Mexico pod-type green chile fruit size, plant architecture, and mechanical harvest efficiency. Two commercial New Mexico pod-type green chile cultivars, NuMex Joe E. Parker and AZ-1904, were direct-seeded on 17 Apr 2015 and 14 Apr 2016. On 11 Jun 2015 and 14 Jun 2016, three plant density treatments were implemented at 39,000 (high), 23,000 (medium), and 15,000 (standard) plants/acre. Before harvest, plant measurements, including height, width, height to first bifurcation, stem diameter, and number of lateral basal branches, were obtained. Plots were mechanically harvested using an inclined double helix harvester, and harvested material was sorted into marketable green fruit, machine-broken fruit, and nonpod plant material. Fruit measurements, including fruit weight, width, length, pericarp thickness, and number of locules, were obtained. Both cultivars exhibited a 9% increase in height to bifurcation accompanied by fewer basal branches grown at high density. Plant density did not significantly affect the fruit length, width, number of locules, and pericarp thickness. Plants grown at high density had an increased percentage of marketable fruit, with ‘NuMex Joe E. Parker’ having a higher percentage of marketable green fruit compared to ‘AZ-1904’. The results demonstrated that an increase in planting density in production fields to 39,000 plants/acre coupled with cultivar selection enhanced efficiency in a mechanical harvest system.