The crop at the MicroFarm is showing increasing variability. The cause of some is understood, essentially excessive water pre-germination. But in some poor performing areas the causes have yet to be determined.
The effect of our artificially applied rain event pre-emergence is clearly evident in late November.
However, we also see other areas that have poor crop development that are outside the area irrigated to create the artificial rain event.
Sharp differences in crop growth are evident in the new onion ground. Some parts that were heavily irrigated to simulate heavy rain show reasonable development. Areas that were not irrigated also show good development, but in some patches total crop loss.
Investigations of soil physical properties in these different areas are underway.
Excitement is being generated at conferences, farmer’s workshops and the general media about the next level in precision agriculture: field robots. We all know that robots work in factories to carry parts or conduct specific actions in manufacturing and that indoor robots are already standard technology in many industries.
There is also interest in developing autonomous equivalents in agriculture beyond the current tractor-carried or self-propelled equipment. There are already some tomato and cucumber picking robots in use in greenhouses in Europe and North America. However, stepping out of the ‘controlled’ environment of a factory building or a greenhouse into the unforgiving conditions of an arable field, a pasture or an orchard poses many serious challenges for scientists and engineers.
Most of these technical challenges have been solved or at least solutions are prototyped for outdoor conditions. This includes the exact positioning and the orientation of the robot under changing ambient light and weather or infrastructure, the recognition of the dynamically changing environment of a field robot as well as precisely controlling the actions that a robot has to conduct in a highly variable environment.
With these preconditions in mind, it is most likely that agricultural robotics will develop very fast in the next years. It is unclear what the first major applications may be and what challenges farmers will face when it comes to using such robots as standard equipment. From discussions with farmers, growers and the industry it is anticipated that weeding robots for row crops (annual field crops, perennial tree and vine crops) will be a good candidate to pave the way for field robots into agriculture.
The presentation will give an overview of current prototypes and weeding robots which are commercially available. We will discuss general differences between these robots and the type of applications that are intended.
As part of the Onions NZ project “Benchmarking Variability in Onion Crops” a process was developed to generate yield and profit maps. This presentation explains the process using the example of a 7.3 ha paddock in Hawke’s Bay.
Data from a satellite image captured in late November were used to identify high, medium and low biomass zones. Paddock yield samples were taken from these zones at harvest and used to generate a paddock yield map. The average yield of the paddock was estimated at 95 t/ha, with a predicted total field harvest of 669 tonnes. This compares to the grower recorded harvest of 614 tonnes.
The relative yield data were combined with grower supplied costs and returns to determine gross margins across the paddock. Data were mapped in ArcGIS and a Gross Margin map with five “profit bands” produced. The highest band had a mean Gross Margin of $11,884/ha compared to the lowest at $3,225/ha.
The breakeven gross margin yield is estimated to be 62.5 t/ha at current costs and prices. The estimated cost to business of low performing areas is $27,945, assuming the whole paddock could achieve the top band mean yield.
The poorest performing areas were identified by the grower as impacted by a failed council drain and areas of slowed drainage in the main paddock areas. An OptiSurface® assessment using historic HBRC LiDAR elevation data analysed of the impact of ponding on the site and also suggested ponding was a significant issue.
An OptiSurface® landform assessment was conducted using both single plain and optimised surface designs and the soil movement required to allow effective surface drainage was determined.
The assessment showed ponding could be avoided by land shaping with 224 m3/ha soil movement and few areas requiring more than 100 mm cut or fill. The cost is estimated at $2,000/ha or approximately $14,000 total.
The New Zealand onion industry expects to further develop high value export markets, particularly in Asia, which could see its exports double to $200million by 2025. To realise these export opportunities the industry needs to improve efficiency and consistency of production and reliably supply high quality onions.
Currently industry average yields for brown onions vary between 33 and 50t/ha depending on season, which are significantly below demonstrated potential average yields of 100t/ha. Competition for productive land mean growers must maximise both productivity and crop value, while also meeting requirements to sustainably use resources and minimise environment impacts.
To help the industry achieve these objectives Onions New Zealand developed a project ‘Enhancing the profitability and value of NZ onions’, in collaboration with LandWISE Inc and Plant and Food Research, to understand causes of low yields and variable quality of onion crops and to develop tools to help growers monitor and manage crops. The project received additional funding from Ministry of Primary Industries Sustainable Farming Fund and commenced in July 2015.
In the first season of the project a crop of cv Rhinestone onions was grown on the LandWISE MicroFarm to allow easy access for both LandWISE and Plant and Food Research scientists to assess crop development and test methods and tools for monitoring the crop and environment at regular intervals.
Four monitoring zones were established across the trial paddock for detailed measurement of plant growth and crop development. Several tools and techniques were tested for obtaining digital data of site and crop attributes.
An important part of the project is the involvement of local growers in discussion of progress results and use of monitoring tools and advice on crop management.
Final potato crop yield is a sum of its parts; each individual plant contributes to it. Should some of these individuals perform below potential, overall yield will be reduced accordingly. Yield variation within a crop is caused by biotic and abiotic factors, which could range from the wholesale effect of soil compaction restricting root growth across the entire field or be an outbreak of patches of disease causing the early death of individual stems or plants.
Nationally, potato yields average 55- 60 t/ha, which are not economically sustaining for many growers, and well below the 80-90 t/ha potential yields predicted by crop models. This was confirmed in a Canterbury survey of 11 process crops in the 2012-13 season where the crops had different histories, management and cultivars. All crops had a similar overall rate of yield reduction, largely caused by soil borne disease and soil physical constraints.
The survey showed that individual groups of healthy plants in a crop did achieve up to 90 t/ha (Fig. 1). However some groups of plants yielded as little as 30 t/ha, due to Spongospora and Rhizoctonia infection, soil compaction and/or inferior seed quality.
Last year, an intensive study of three Canterbury crops showed that some areas of the crops reached potential and that others were limited by soil borne disease infection and water supply.
A field experiment at Lincoln is currently investigating how bed shape, subsoiling and irrigation regime are affecting crop production, and future work will look at how improvements to seed tuber production could reduce yield variability.
Given there are two dozen top Australian growers, agronomists and researchers joining us for our conference, arranging more time to discuss issues of interest was too good an opportunity to pass up.
The programme for the day is less structured than a normal conference day. The morning is inside discussion, the afternoon getting out and about. But it does follow two days of conference, so we’ll be well primed.
We will spend time discussing some key crops – onions and potatoes included – and importantly technologies we can use to better understand and manage them.
We aim to identify areas of common interest and possible collaboration. What topics are relevant in both countries? What joint research opportunities are there? Where to from here?
After lunch we travel to a local farm, True Earth Organics, where Scott and Vicki Lawson and staff grow and pack a range of field, vegetable and berry crops. From there we go to a local major vegetable processing factory to view the next stage in the value chain.
This winter we have established both Caliente Mustard and Oats in paddocks 1 and 2, the site of our last two years of summer onions.
The ground had not had onions before 2014-2015 as far as we know. We grew our second crop in succession in 2015-2016.
Our plan is to grow onions for a third year, and to pay attention to the development of weeds, pests and diseases. Plant and Food Research reported some evidence of “Pink Root” in a few plants while harvesting samples of the 2015-2016 crop.
After harvest, Gerry and John Steenkamer ripped the beds, leaving the wheel tracks. This is step 1 of a route into permanent bed cropping at the MicroFarm.
Unfortunately, the alignment of the main AB line for the entire block did not match the buried drip irrigation installed some years ago, and it has been damaged beyond repair.
After ripping, Mike Kettle Contracting power harrowed the paddocks to about 100mm to reduce the rubbley surface. The Caliente and Oats were drilled by Kettle Contracting on 16 March.
We chose a split-paddock planting, with Caliente on the northern side and oats on the south. This repeats last winter’s pattern, so we will have two years of onions followed by either Caliente or Oats when we establish the 2016-2017 crop.
Many thanks to True Earth Organics for supplying the Caliente seed, and to G & J Steenkamer and Mike Kettle for groundwork and drilling.
LandWISE farmers and processors want to increase vining pea yields, and importantly reliably higher yields. Last year many farms growing processing pea crops exceeded 10t/ha. But regularly crop yields are less than half that.
We have been trying to determine factors controlling plant density, flowering, pod number, pea number and fill in process crops. Unlike seed peas, vining peas are harvested before the life cycle is complete. Any variation in maturity causes yield loss – both quantity and quality.
A small trial at the MicroFarm saw three lines of Ashton pea seed planted on the same day, using the same drill, seeking to achieve the same plant density of 110 plants/m2.
Sub-plots in each line were covered in Cosio cover mesh or an open bird netting to remove the effect of birds stealing seed or seedlings. This is important because recent years have seen a major increase in bird numbers and damage. We had 60 pigeons eating a 1ha crop. One farm shot 600 pigeons on one crop in one day and there were still hundreds eating.
At emergence, striping effects were immediately noticeable. We attribute this to drill settings because it repeated at the same spacing across the paddock. Half the width emerged later than the rest. What surprised us was the length of delay in some areas, plants emerging up to three weeks behind.
On enquiry, we found the coulters were set differently to account for the area compacted by the tractor tyres versus uncompacted/untrafficked areas. The settings were clearly incorrect!
The trouble with this kind of issue is the delay in observing the problem. In the period between planting this crop and our observation, many, many other crops could have been planted, all to suffer a similar problem.
How big is the problem?
We’ll take samples from the three seed lines, the cover options and the planter positions just before harvest. We’ll determine their yields and see what variation we find.
Dr Jane Adams, OnionsNZ Research and Innovation Manager, says the project, “Enhancing the profitability and value of New Zealand onions” is designed to provide the industry with tools to monitor and manage low yields and variability in onion yield and bulb quality.
It will incorporate precision agriculture with initial work to be done at the LandWISE MicroFarm. At the MicroFarm, we have been building increasing knowledge of the site, but will ramp that up with more layers of soil and crop information as we try to unpick factors contributing to lower yields and reduced quality.
Information about the 2014-2015 MicroFarm Onion crop can be found on the MicroFarm website.
The project proper starts on 1 July, but there has a lot of preparatory activity to ensure everything kicks of smoothly.
Anyone interested in joining a regional Focus Group supporting the project should contact us>