Biodegradable plastic mulch has the potential to be a sustainable technology in agricultural production systems if the mulch performs equally to polyethylene (PE) mulch and biodegrades completely into constituents that do not harm the soil ecology or environment. Reduced labor costs for removal and disposal, and reduced landfill waste add further appeal to the sustainability of biodegradable plastic mulch. Biodegradable paper mulch has been allowed in certified organic production systems in the United States for many years, while the National Organic Program (NOP) added biodegradable biobased plastic mulch to the list of allowed synthetic substances for organic crop production in Oct. 2014. Although biodegradable plastic mulch may meet the NOP biodegradability requirements (90% biodegradation within 2 years), currently no products have been approved for use in certified organic production because, so far, none meet the requirement of being completely biobased. Additionally, while the synthetic manufacturing processes that are used to make biodegradable plastic mulch are allowed by the NOP, the use of genetically modified organisms (GMOs) in the feedstocks, including their fermentation, is not allowed. Organic growers are advised always to check with their certifier before applying a product as some biodegradable mulch manufacturers and marketers erroneously advertise their product as “organic.” Looking forward, if biodegradable plastic mulch meets the NOP requirement of 90% biodegradation after 2 years, there is a possibility that 10% of plastic mulch residuals will persist (if the mulch contains nonbiodegradable ingredients); in this case, after 8 years of annual biodegradable mulch application, plastic residuals in the soil would exceed twice the amount of mulch applied per year. The current methods used by the NOP to test mulch biodegradation are laboratory based and it is uncertain if the results accurately represent field conditions. Reliable field sampling methods to measure residual mulch fragments in the soil need to be developed; however, it is unlikely such field tests will measure CO ₂ evolution, and thus will not be a true measure of biodegradation. Additional testing is needed under diverse field conditions to accurately quantify the rate and extent of biodegradation of mulch products that are marketed as biodegradable.

Four potentially biodegradable mulch products (BioAgri, BioTelo, WeedGuardPlus, and SB-PLA-10) were evaluated during 2010 in three contrasting regions of the United States (Knoxville, TN; Lubbock, TX; and Mount Vernon, WA) and compared with black plastic mulch and a no-mulch control for durability, weed control, and impact on tomato yield in high tunnel and open field production systems. WeedGuardPlus, BioTelo, and BioAgri had the greatest number of rips, tears, and holes (RTH) and percent visually observed deterioration (PVD) at all three sites ( P ≤ 0.05), and values were greater in the open field than high tunnels, likely as a result of high winds and greater solar radiation and rainfall. SB-PLA-10 showed essentially no deterioration at all three sites and was equivalent to black plastic in both high tunnels and the open field. Weed growth at the sites did not differ in high tunnels as compared with the open field ( P > 0.05). Weed growth at Knoxville and Mount Vernon was greatest under SB-PLA-10 ( P ≤ 0.02), likely as a result of the white, translucent nature of this test product. Tomato yield was greater in the high tunnels than open field at all three sites ( P ≤ 0.03), except for total fruit weight at Knoxville ( P ≤ 0.53). Total number of tomato fruit and total fruit weight were lowest for bare ground at both Knoxville (150 × 10 ⁴ fruit/ha and 29 t·ha ⁻¹ ; P ≤ 0.04) and Mount Vernon (44 × 10 ⁴ fruit/ha and 11 t·ha ⁻¹ ; P ≤ 0.008). At Knoxville, the other mulch treatments were statistically equivalent, whereas at Mount Vernon, BioAgri had among the highest yields (66 × 10 ⁴ fruit/ha and 16 t·ha ⁻¹ ). There were no differences in tomato yield resulting from mulch type at Lubbock.

We conducted a blind tasting sensory evaluation experiment and a chemical analysis of four craft hard apple ciders from the Pacific Northwest of the USA. Using the sensory and demographic data collected during the experiment, we estimated the consumer willingness-to-pay (WTP), using a contingent valuation model. Overall liking, taste, and aroma, from the sensory evaluation, as well as age of the sampler and if the sampler was a cider drinker, contributed positively to the WTP. In contrast, if the subject was a beer drinker this reduced their WTP. From the chemical analysis we found that tannin level had a positive effect on WTP, but an increased level of sweetness, as part of a ratio of specific gravity to acid, decreased consumer WTP. (JEL Classifications: C91, D12, L66, Q13)

Watermelon (Citrullus lanatus) grafting has emerged as a promising biological management approach aimed at increasing tolerance to abiotic stressors, such as unfavorable environmental conditions. These conditions include environments that are too cold, wet, or dry, have soil nutrient deficiency or toxicity and soil or irrigation water salinity. Studies to date indicate that fruit yield and quality may be positively or negatively affected depending on rootstock-scion combination and growing environment. Growers need information regarding the general effect of rootstocks, as well as specific scion-rootstock interactions on fruit maturity and quality so they can select combinations best suited for their environment. This review summarizes the literature on watermelon grafting with a focus on abiotic stress tolerance and fruit maturity and quality with specific reference to hollow heart and hard seed formation, flesh firmness, total soluble solids, and lycopene content.

Grafting watermelon (Citrullus lanatus) onto resistant rootstocks is an effective technique in the management of biotic and abiotic stresses. Since the first reported grafting of watermelon for disease resistance in 1927, adoption of the practice has been steadily increasing up to 95% in Japan, Korea, Greece, Israel and Turkey. However, for grafting to be further adopted in the United States and other regions of the world with high labor costs and high plant volume demands, the watermelon grafting method must be more time and labor efficient as well as suitable for automation. To accomplish these goals, recent advances have been achieved in splice grafting of watermelon, where both cotyledons are removed from the rootstock. This review provides a summary of the new discoveries regarding watermelon grafting and an overview of the anatomy of cucurbit stems and the physiological processes that occur at the time of grafting and during the healing process in order to enhance the understanding of the complex nature of the cucurbit vascular system, which limits grafting success. This review article further provides insights to guide future research and technology development that will support the expansion of watermelon grafting.

Plastic mulches have become an essential component of modern agriculture since their introduction in the 1950s. However, disposal of plastic mulches poses serious environmental challenges as plastics that are not considered biodegradable or compostable can take several hundred years to degrade. Each year in the United States, only 9% of overall plastic waste is recycled while 79% is accumulated in landfills or the natural environment. Recycling of plastic mulch is especially constrained due to the contamination that results from their use in farming. Currently, recovered mulches are reported to have 30%–80% surface contamination, primarily from soil and plant debris. Plastic mulch waste is concentrated in areas where they are used and can provide logistical opportunities to the plastic recycling industries. Plastic recycling includes mechanical, advanced (chemical and thermal), and biological methods, that may all be used for polyethylene (PE). Most plastic is recycled using the mechanical method, while advanced and biological methods are promising but face significant financial and technical challenges. For all recycling methods, strategies are needed for managing surface contamination to realize the recycling potential of plastic mulch.