Plant breeding is a pragmatic applied science, you know, taking genetic raw
materials and turning them into something useful. Our research is really
relevant to climate change because the breeding approaches we're taking are for
the future, so we want varieties for the future. The goal of the plant breeder is
to think about an endpoint. So you start with a goal in mind, and you reach that
goal, and then a new goal arises and it sort of renews itself, and you keep going
But also they have long-term goals as far as renewing their germplasm
tools and raw materials to ensure that there's adequate
genetic variability to meet the challenges of things like climate change
that are largely unknown. Climate is changing and one of the things
especially for a plant breeder is you don't know exactly what those challenges
might be in the next 10, 15, 20 years, whether it's disease, whether it's heat
tolerance, whether it's drought tolerance, you know, whatever it's going to be. By
maintaining that diversity, hopefully somewhere within that germplasm pool
you will have the genes that you need to be able to put together and create new
varieties that have those tolerances. The only way for us to be able to meet this
challenge is to be able to collect and to preserve as much biodiversity,
genetic variability, as we possibly can, and plant breeders are the most
important preservers of biodiversity.
Problems that relate to climate change
from the standpoint of plants and
agriculture I think are heat stress and
disease pressure. As the climate changes, one can say the whole ecology changes
and that there are probably diseases and insects that
we currently do not have today that will appear on the
horizon and create new challenges that we're not
even aware of today. The milder winters
will increase the fungal and insect
pests for sure. I lived in Oregon 23 years and they have a mild climate there,
and their diseases always hit earlier on rust, for example, than ours, but lately
rust has become a bigger problem here.
The drought tolerance work that we're
doing is important. We're working on salinity tolerance so as our water
resources continue to sort of disappear and dry up we need to have alternate
sources of irrigation and especially for turf grasses. So, you can use a lot of our
waste water that is normally just discarded, we can use that to irrigate.
Then the milder winters will certainly affect the plants themselves,
specifically if we have hotter wetter summers. It will definitely affect
the, I think, the annuals—things like tomatoes, peppers and eggplants. We refer
to them as being warm-season and heat-loving crops, but in fact
they don't like excessive heat. They shut down and don't grow. They don't set fruit.
The flowers drop off. It's a stressful condition to them. Climate change
impacts the adaptation of the cultivars that we grow here in New Jersey. I would
say enhanced heat and the longer periods of heat incite more fruit rot
pressure, which is probably the biggest issue here in the state. Not only that
but we're seeing more and more invasive diseases and pests come in
from other parts of the world and get themselves established here.
If you look at the native distribution of
cranberries they occur from largely south New Jersey out to eastern
Minnesota and southeast Canada, and so we, New Jersey, really represents the most
southern adaptation zone for the wild cranberry. So as the climate is getting
warmer, that adaptation zone may be moving further north. And both crops I happen to work with, blueberries and cranberries, require what we call
winter chilling. The plants have essentially like an internal mechanism
where they count the amount of chilling hours. Certain plants need to
accumulate cold temperatures in order to break dormancy in the spring—so there's
a period of time above freezing but below maybe 45 degrees Fahrenheit.
Temperatures below freezing actually do not contribute to the chilling. The only
temperatures that are above freezing that contribute to the chilling.
And, in fact, some of our warmest winters
actually had the most chilling hours.
But if we look out 20, 30 years or maybe 50 years in the future,
varieties that we are growing today may not be adequate for those conditions up and coming.
The rate of climatic change is a huge challenge
because we need to be able to have some time to gather the genes,
because most of the genetic systems that
control crop performance under different climatic conditions are very complicated
genetically. They take time to unravel, and, that said, I'm absolutely convinced
and optimistic that we're going to be able to meet this challenge
because there is a tremendous amount of genetic variability out there.
As breeders we make a hierarchy list of, say, traits or
characteristics or problems we're trying to deal with, and I think that climate
change needs to be pushed all the way to the top.
As long as resources to maintain these programs are provided and the breeders
can continually select out the most adaptive materials and breed with them
then there's hope that we can develop varieties that are going to be suited
for the new conditions or a climate that we'll be experiencing the next, you know,
several decades or so. With hazelnuts I
think we have a species that will provide us a really good opportunity to
develop new cultivars able to withstand the unpredictable nature of climate change
There's a wealth of genetic diversity. You can find plants growing as
far south as Morocco and as far north as into Scandinavia north of Moscow.
So we can take plants from very far south and hybridize them with plants
from the very northern fringe regions. Those offspring—some of those
offspring—may have the ability to be very widely adapted. These are not just, you
know, exercises in scientific theory. The breeding program here directly addresses climate
change because we're basically selecting out varieties that
are adapted to the warmer temperatures both in the winter and in the
summer here and the stresses that the higher temperatures impose. And the
varieties that are developed are being
utilized by the grower and in the industry. We have so many more powerful
tools at our disposal to be able to access genes, to isolate them, to
understand how they express, how they interact with other genes, how they
interact with the environment. Every few months there's some new technique that
makes everything go faster, and as we make DNA sequencing and genome
sequencing faster and cheaper it's going to be become more and more reasonable
for any plant breeder to be able to use these techniques.
The farmers really aren't thinking about it. They're so caught up in the
day-to-day of how am I going to get past this broken tractor and how am I going
to, you know, get my pesticide out, it's
raining out, for them to focus on
something as broad based and long-term as climate change is very, very difficult for them. And it's another
good reason why I think it's something that we need to focus on in a place like
a land-grant university, because there's very few other places in our society
that we have the luxury of being able to look in the long term, because this is
going to be a challenge I think for humankind and I feel privileged that
we're in a place like a land-grant university that we can start to think about this.
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