Latest News Archive

Please select Category, Year, and then Month to display items
Previous Archive
31 July 2020 | Story Lacea Loader
Moderator and Panellists

As a public higher-education institution in South Africa with a responsibility to contribute to public discourse, the University of the Free State (UFS) will be presenting the 3rd UFS Thought-Leader Series in collaboration with Vrye Weekblad as part of the Vrystaat Literature Festival’s online initiative, VrySpraak-digitaal.

This year, higher-education institutions globally are placed in the challenging context of COVID-19. Aware and grounded in the reality that the world will not return to the normality of pre-COVID-19, our responsibility as scholars still remains to contribute to public discourse and to offer innovative solutions that will impact the lives of people nationally and globally in order to help them understand and adapt to a new world order.

Against this background and context, this year’s debates focus on ‘Post-COVID-19, Post-Crisis’, with Health and Modelling, Politics, Economy, and Predictions for 2021 as the sub-themes. Placed in a COVID-19 context, and in lieu of the Vrystaat Arts Festival, the series will be presented virtually in the form of one webinar per month during the period August 2020 to November 2020.

Date: 13 August 2020
Topic: Health and Modelling
Time: 11:30-13:00
RSVP: Alicia Pienaar, pienaaran1@ufs.ac.za

Facilitator:

Max du Preez
Editor: Vrye Weekblad
Biography

Introduction and welcome:

Prof Francis Petersen
Rector and Vice-Chancellor, UFS

Panellists:

Prof Salim Abdool Karim
Director: Centre for the AIDS Programme of Research in South Africa (CAPRISA)
Chair: South African Ministerial Advisory Committee on COVID-19
Biography

Prof Glenda Gray
President and CEO: South African Medical Research Council (SAMRC)
Biography

Prof Felicity Burt
NRF-DST South African Research Chair in vector-borne and zoonotic pathogens research
Biography

 

 

News Archive

Sunflowers are satellite dishes for sunshine, or are they?
2016-07-20

Eighty-six percent of South Africa’s
sunflowers are produced in the
Free State and North West provinces.

Helen Mirren, the English actress, said “the sunflower is like a satellite dish for sunshine”. However, researchers at the University of the Free State (UFS) have found that too much of this sunshine could have a negative effect on the growth of sunflowers, which are a major source of oil in South Africa.

According to Dr Gert Ceronio from the Department of Soil, Crop, and Climate Sciences at the UFS, extremely high soil temperatures play a definite role in the sprouting of sunflower seedlings. Together with Lize Henning, professional officer in the department, and Dr André Nel from the Agricultural Research Council, he is doing research on biotic and abiotic factors that could have an impact on sunflowers.

Description: Sonneblom 2 Tags: Sonneblom 2

Various degrees of deformity (bad-left
to none-right) in seedlings of the same
cultivar at very high soil temperatures.
Photo: Dr Gert Ceronio

Impact of high temperatures on sunflower production

The Free State and North West provinces, which produce 86% of South Africa’s sunflowers, are afflicted especially by high summer temperatures that lead to extremely high soil temperatures.

Dr Ceronio says: “Although sunflower seeds are able to germinate at temperatures from as low as 4°C to as high as 41°C, soil temperatures of 35°C and higher could have a negative effect on the vegetative faculty of sunflower seedlings, and could have an adverse effect on the percentage of sunflowers that germinate. From the end of November until mid-January, this is a common phenomenon in the sandy soil of the Free State and North West provinces. Soil temperatures can easily exceed the critical temperature of 43°C, which can lead to poor germination and even the replanting of sunflowers.”

Since temperature have a huge impact not only on the germination of sunflower seeds, but also on the vegetative faculty and sprouting of sunflower seedlings, Dr Ceronio suggests that sunflowers should be planted in soil with soil temperatures of 22 to 30°C. Planting is usually done in October and early November. Unfortunately, this is not always possible, as soil moisture is not optimal for growth. Farmers are then compelled to plant sunflowers later.

Impact of herbicides on sunflower growth

“High soil temperatures, combined with the herbicide sensitivity of some cultivars, could lead to the poor development of seedlings," says Dr Ceronio.

The use of herbicides, such as ALACHLOR, for the control of weeds in sunflowers is common practice in sunflower production. It has already been determined that ALACHLOR could still have a damaging effect on the seedlings of some cultivars during germination and sprouting, even at recommended application dosages.

“The purpose of the continued research is to establish the sensitivity of sunflower cultivars to ALACHLOR when exposed to high soil temperatures,” says Dr Ceronio.

 

We use cookies to make interactions with our websites and services easy and meaningful. To better understand how they are used, read more about the UFS cookie policy. By continuing to use this site you are giving us your consent to do this.

Accept