Barrios Masias, F., Kratsch, H. 2024, Melon Grafting and Irrigation, Desert Farming Initiative - University of Nevada, Reno

This research evaluates the effects of grafting and irrigation management on melon production at the University of Nevada, Reno - Valley Road Experiment Station (including collaboration with Desert Farming Initiative melon trials) and at Lattin Farms in Fallon, Nevada. This project was funded by the Western Sustainable Agriculture Research and Education (SARE) program (award SW20-918). The full title of the project is “Enhancing melon production and adaptation in high desert environment through grafting on squash hybrid rootstocks”.

The project included an initial survey of primarily Nevada growers to explore their interest in using grafting to enhance crop performance and help them address some of the challenges they face in growing crops, such as drought and water availability. 

We conducted field and greenhouse trials to understand how commercial rootstocks can impact the performance of melons in two distinct environments of northern Nevada (i.e., Fallon and Reno). In addition, we studied how different irrigation volumes affect melon performance and yield with the objective to determine if growers could reduce the amount of applied water without a yield decrease. The study recognized that reduction in irrigation volumes can result in increased water use efficiency (i.e., pounds of melon per volume of irrigation water).

Experimental Design

The project trials were conducted during three field seasons (2021 – 2023) to replicate experiments over time and locations, and data was statistically analyzed to provide growers with results that can support decision making at the farm level.

Rootstock trials:

  • Nine rootstocks were grafted with a common scion cultivar (Sarah’s Choice).
  • The rootstocks were commercial squash-hybrids from the cross between Cucurbita maxima x C. moschata: Carnivor, Bs1, Tz148, Just, Rs841, Aq, Ercole, Cobalt and Shintosa (more information at USDA-NIFA, 2015).
  • The ungrafted cultivar (Sarah’s Choice) was used as a control as this would be the usual practice for growers in the area.
  • Each trial had a randomized complete block design (RCBD) with each plant material (grafted and ungrafted plants) having a minimum of six plots (replicates) and six plants within each plot.
  • Plant spacing was three feet between plants and seven feet between rows.

Irrigation trials:

  • The experimental design was similar to the rootstock trials: an RCBD with six replicates per treatment.
  • The treatments were irrigations to replenish soil moisture to 100%, 70% and 50% of field capacity.
  • Water requirement per irrigation were calculated from soil moisture sensor readings placed at 8” and 16” deep in the soil.

Results and Findings

Our main results are presented here, and links are provided below for more detailed information.

Rootstock Trials:

  • Grafting for Cantaloupe melons in the high desert did not provide a consistent advantage over the ungrafted cultivar.
  • Location and year had a strong effect on yield, fruit weight and fruits per plant.
  • Fruit quality (sweetness) was consistently high in the ungrafted cultivar.
  • Our trials suggest that grafting to some rootstocks may confer earlier harvests.

Irrigation Trials:

  • Crop water productivity (pounds of melon per inch of water applied) was increased at the 70% and 50% irrigation treatments.
  • Yield was similar between the 100% and 70% irrigation treatments, but the 50% treatment had a significant decrease in yield.
  • It is possible to reduce irrigation volumes by ~30% of crop evapotranspiration without compromising yields.
  • The use of soil moisture sensors could provide a tool to better determine crop water needs, but this warrants further evaluation based on crop and management conditions.

Further information:

We will update this information as our work continues! Below are presentations and further materials related to the work described above. Please email Dr. Barrios Masias for access to these resources at fbarriosmasias@unr.edu

Acknowledgments 

This material is based upon work that is supported by the National Institute of Food and Agriculture, U.S. Department of Agriculture, under award number 2019-38640-29880 through the Western Sustainable Agriculture Research and Education program under project number SW20-918. USDA is an equal opportunity employer and service provider. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture.

Learn more about the author(s)

 

Also of Interest: