A study was conducted to assess effects of irrigation on yield and quality of photoperiod sensitive (PS) and non-PS forage sorghums in comparison to corn in central Wisconsin. Treatments were arranged as a split-plot with a randomized complete block design with 3 replications. Five irrigation rates (0, 25, 50, 75, and 100%) relative to corn water needs were applied using a linear irrigation system with each rate applied as one strip. For practical purposes, the 0% rate was in a different field at the station with a similar soil type. Irrigation rates were attained using irrigation nozzles with different flow rates. Within irrigation rate strip, cultivars (corn, PS forage sorghum, PS sorghum-sudangrass, forage sorghum, BMR forage sorghum, sorghum-sudangrass, BMR sorghum sudangrass, PS BMR sudangrass) were randomly assigned within 3 replicate blocks. Plots were established June 2, 2016 and harvested using a single harvest at 1/3 to 1/2 corn kernel milk-line, soft to hard-dough stage or after a frost for sorghums. Data were analyzed using the MIXED procedure of SAS 9.4. Precipitation as rain was 62.2 cm; irrigation totals were 7.4, 14.9, 22.4, and 29.8 cm for 25, 50, 75, and 100% rates, respectively. Cultivars interacted with irrigation rate (Table 1; P = 0.04) with PS varieties and BMR forage sorghum most responsive to greater irrigation rates, corn having moderate responses, and forage sorghum, sorghum-sudangrass and sudangrass being less responsive. This may be due to PS varieties exhibiting no reproductive growth until harvest. Sorghum-sudangrass and forage sorghum have potential to be grown with less irrigation and have high forage yields. Table 1. DM yields (kg/ha) for sorghums and corn at various irrigation rates

Variety	Irrigation rate (%)
	0	25	50	75	100
Corn	15,508	15,053	17,338	19,301	22,452
PS forage sorghum1	20,384	23,498	35,407	39,782	37,438
PS sorghum-sudan	21,108	26,917	31,666	38,752	44,457
Forage sorghum	26,089	24,707	25,163	26,805	31,465
Sorghum-sudan	19,787	19,249	25,095	25,977	21,691
BMR forage sorghum	15,915	22,624	21,273	29,837	34,787
BMR sorghum-sudan	18,510	18,928	19,428	18,674	24,633
PS BMR sudangrass	21,280	23,378	19,749	28,426	24,603
SEM			3,536
Variety × Irrigation (P-value)			0.04

¹PS = photoperiod sensitive.