Phenotypic Characteristics of Ten Garlic Cultivars Grown at Different North American Locations

Abstract

Garlic (Allium sativum L.) cultivars grown under diverse conditions have highly elastic environmental responses, particularly relating to skin color and yield. Ten diverse garlic cultivars were grown at 12 locations in the United States and Canada for 2 consecutive years to identify the environmentally responsive phenotypic traits of garlic. Clove arrangement, number of topsets, topset size, topset color, number of cloves, clove weight, clove skin color, and clove skin tightness were generally stable for each cultivar regardless of production location and conditions. Scape presence varied with cultivar and location, but for the most part, cultivars classified as hardneck types produced scapes and those classified as softnecks did not produce scapes. Bulbs grown at the northern Colorado, Minnesota, Pennsylvania, Vermont, and Washington locations were generally larger than the other locations. Soil potassium levels were positively correlated with bulb circumference and fresh weight. Soil sulfur and manganese levels were correlated with bulb sulfur and manganese content. Bulb wrapper color and intensity were highly dependent on location and cultivar. The Silverwhite cultivar was consistently white and ‘Ajo Rojo’, ‘German White’, ‘Inchelium’, ‘Sakura’, and ‘Spanish Roja’ were generally white with some faint violet or brown stripes or splotches across the locations. In contrast, cultivars Chesnok Red, Purple Glazer, Red Janice, and Siberian were more likely to have moderate or dark violet stripes, streaks, or splotches, particularly when grown at the northern Colorado, Minnesota, Nevada, New York, Ontario, Pennsylvania, or Washington locations. These results can help farmers identify niche regional markets that provide novel products to consumers. From these results, it was shown that garlic cultivars or classes grown under diverse conditions have highly elastic soil nutrient responses, particularly relating to skin color and yield.